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THE INSTITUTE 
OPHTHALMOLOGY 

LONDON 

EX LIBRIS 




2 £Uk3*fT& 



0^ 




DISEASES OF THE EYE. 



I. i 



1 




A HANDBOOK 



OF THE 



DISEASES OF THE EYE 



AND THEIR 



TREATMENT 



HENRY R. SWANZY, A.M., M.D., (Causd hon.) Univ. Dub. 

PRESIDENT OF THE ROYAL COLLEGE OF SURGEONS IN* IRELAND, 
EX-PRESIDENT AND BOWMAN LECTURER OF THE OPHTHALMOLOGICAL SOCIETY OF 
THE UNITED KINGDOM, SURGEON TO THE ROYAL VICTORIA EYE AND EAR HOSPITAL, AND 
OPHTHALMIC SURGEON TO THE ADELAIDE HOSPITAL, DUBLIN. 



LOUIS WERNER, M.B., F.R.C.S.I., Sen. Mod. Univ. Dub. 

OPHTHALMIC SUROKON TO THE MATER HOSPITAL, ASSISTANT SURGEON TO THE 
ROYAL VICTORIA EYE AND EAR HOSPITAL, EXAMINER IN OPHTHALMIC SURGERY 

UNIVERSITY OF DUBLIN AND ROYAL UNIVERSITY OF IRELAND, 
LECTURER IN OPHTHALMOLOGY CATHOLIC UNIVERSITY MEDICAL SCHOOL, DUBLIN. 



NINTH EDITION 

WITH ILLUSTRATIONS 



LONDON 

II. K. LEWIS, L36 GOWER STREET, W.C. 

1907 



London 

U. K. Lewir; 136 Gower Stkeet, W.C. 



THIS- BOOK IS DEDICATED 

TO 

THEODOR LEBER, 

Professor at the University op. Heidelberg, 
AS A MARK OF 
ADMIRATION FOR HIS EMINENT SERVICES 

TO OPHTHALMOLOGY. 



Digitized by the Internet Archive 
in 2014 



https://archive.org/details/b21641262 



PREFACE TO THE NINTH EDITION. 



— ♦ — 

This work now appears under joint authorship. In preparing 
the present edition, the endeavour has again been to keep 
the book abreast of modern ophthalmology — in so far as is 
possible, without adding to its size — by discarding what had 
become obsolete, and by introducing important new develop- 
ments. That there are more pages in this edition results, 
mainly, from the greater number of illustrations contained 
in it, being sixty more than in the previous edition. More- 
over, in compliance with very generally expressed wishes, 
a chapter on elementary optics has been introduced, and the 
optical structure of the eye, refraction and accommodation, 
and the theory of the ophthalmoscope have been treated of 
with more completeness. Chapter v. now contains an account 
of the bacteriology of conjunctivitis ; chapter xvhi. has been 
improved, and a description of heterophoria added ; and 
many other alterations have been made throughout the book. 

H. R. S. 
L. W. 

Dublin, 

January 1907. 



CONTENTS 



CHAPTER I. 

ELEMENTARY OPTICS. 

Divergence and Parallelism of Rays of Light — Refraction — Index 
of Refraction — Plane Glass — Prisms — Spherical Lenses (foci 
of, images formed by) — Cylindrical Lenses — Numbering and 
Decentration of Lenses 



CHAPTER II. 

OPTICAL STRUCTURE AND FUNCTIONAL EXAMINATION 
OF THE EYE. 

Note on the Clinical Examination of Eye Patients — Optical Struc- 
ture of the Eye — Normal Refraction and Accommodation — 
Convergence (the Metre Angle) 21 

The Sense of Sight (Light-Sense, Colour-Sense, Form-Sense) — 

The Field of Vision 32 



CHAPTER III. 

ABNORMAL REFRACTION (AMETROPIA) AND ACCOMMODATION. 

Myopia — Definition and Causes of M. — J'unctum Remotum in 
M.— Optical Correction of M. — Diagnosis and Determination 
of Degree of M. — Amplitude and Range of Accommodation 
in M. — Angle Gamma in M. — Etiology of M. — Non-l'rogressive 
M.— Symptoms of M.— Complications of Progressive M. — 
Functional Anomalies attendant upon M. — Management of M. 
— The Prescribing of Spectacles in M. — Operative Cure of M. 45 

ix 



X 



CONTENTS. 



Hypermetropia — Definition, and Optical Causes of H.— Punctum 
Remotum in H. — Optical Correction of H. — Determination of 
Degree of H. — Amplitude and Range of Accommodation in 
H. — Angle Gamma in H. — Varieties of H. — Etiology of H. — 
Symptoms of II. — Accommodative Asthenopia in H. — Internal 
Strabismus in H. — The Prescribing of Spectacles in H. . . K3 

Astigmatism — Varieties of As. — Symptoms of As. — Estimation of 
Degree of, and Correction of As. — The Astigmometer — Lental 
As. — Irregular As. . . . . . . . .71 

Anisometropia 85 

Anomalies of Accommodation — Presbyopia — Paralysis of Accom- 
modation — Accommodative Asthenopia — Spasm of Accommo- 
dation 86 



CHAPTER IV. 

THE OPHTHALMOSCOPE. 

Laws of Reflection — Images formed by Plane and Concave Mirrors 
— How to distinguish Plane and Concave Mirrors — Effect of 
Rotation of a Mirror . . . 94 

Why Necessary — Helmholtz's Ophthalmoscope — Modern Ophthal- 
moscope — -Direct Method — Indirect Method .... 97 

Estimation of the Refraction by Aid of the Ophthalmoscope — Diiect 

Method — Retinoscopy ........ 105 

Detection of Opacities in the Media . . . . • .119 

The Normal Fundus Oculi as seen with the Ophthalmoscope — The 
Optic Tapilla, or Optic Disc— The Retina— The Macula Lutea 
—The General Fundus Oculi— The Retinal Vessels . . . 120 



CHAPTER V. 

DISEASES OF THE CONJUNCTIVA. 

Examination of the Conjunctiva — Hyperemia — Conjunctivitis 
(Causes, Diagnosis, Varieties)— Bacteriology of Conjuncti- 
vitis— Catarrhal Conjunctivitis— Acute Blennorrhea of the 
Conjunctiva, or Purulent Ophthalmia— Membranous Con- 
junctivitis (Croupous and Diphtheritic)— Hay Fever— Trach- 
oma, Grannlar Conjunctivitis, or Granular Ophthalmia (Acute 
and Chronic)— Follicular Conjunctivitis— Parinaud's Conjunc- 
tivitis— Tubercular Disease of Hie Conjunctiva— Ophthalmia 
Nodosa— Lupus— Syphilis — Ulcers of tlie Conjunctiva — 
Spring Catarrh— Conjunctival Complication of Smallpox- 
Hyaline, Colloid, and Amyloid Degeneration — Xeroses — . 



CONTENTS. xi 

I'AOE 

Pemphigus — Pinguecula — Pterygium — Lithiasis' — Conjunc- 
tivitis Petri Scans —Subconjunctival Ecchymosis — Chemosis — 
Injuries of the Conjunctiva — Simple Cysts — Subconjunctival 
i vsticercus — Dermoid Tumours — Dermo-Lipoma— Osteoma — 
Nsevns — Hemangioma — Polypus — Lymphoma — Papilloma — 
Malignant Tumours (Epithelioma, Sarcoma). . , . 127 



CHAPTER VI. 

PHLYCTENULAR CONJUNCTIVITIS AND KERATITIS. 

Solitary, or Simple, rhlyctenula of the Conjunctiva — Multiple, or 
Miliary, Phlyctenula of the Conjunctiva — Modes of Secondary 
Corneal Affection — Primary Phlyctenular Keratitis — Different 
Forms of Same — Symptoms of Phlyctenular Keratitis — Causes 
of Phlyctenular Ophthalmia — Treatment 1 98 



CHAPTER VII. 

DISEASES OP THE CORNEA. 

Clinical Methods of Examining the Cornea — Inflammations of the 
Cornea — (a) Ulcerative Inflammations of the Cornea — Simple 
Ulcer — Deep Ulcer — Serpiginous Ulcer — Diplobacillus Ulcer 
— Kodent Ulcer — Marginal Ring Ulcer — Absorption Ulcer — 
Xeuro-Paralytic Keratitis — Infantile Ulceration of the Cornea, 
with Xerosis of the Conjunctiva — -Herpes Corneae Febrilis 
— Filamentary Keratitis — Bullous Keratitis — Dendriform 
Keratitis— Keratitis Aspergillina .... . . 207 

(h) Non-Ulcerative Inflammations of the Cornea — Abscess — 
King Abscess — Syphilitic Diseases of the Cornea — Keratitis 
Profunda — Grating-like Keratitis, and Guttate Keratitis — Dis- 
coid K. — Tubercular K. — Keratitis Punctata — Sclerotising 



Opacity — Ribandlike Keratitis 239 

Kctasries of the Cornea — -Staphyloma Corneai (Evisceration and 

Mules' Operation) — Conical Cornea, or Keratoconus. . . 253 

Tumours of the Cornea 261 

Injuries of the Cornea — Foreign Bodies — Lo.ises of Substance — 
Recurrent Abrasion, or Disjunction — Blows — Burns— '-Perforat- 
ing Injuries 264 

Opacities of the Cornea — Nebula, Macula, Leucoma — Arcus Senilis 272 



xii 



CONTENTS. 



CHAPTER VIII. 

DISEASES OF THE EYELIDS. 

PAOP. 

Eczema — Marginal Blepharitis (Ophthalmia Tarsi) — Phtheiriasis 
Ciliorum — -Hordeolum (Stye) — Chalazion (Meibomian Cyst, 
Tarsal Tumour) — -Milium — Molluscum — Nsevus — Xanthelasma 
— Chromidrosis — Herpes Zoster Ophthalmicus — Syphilitic 
Affections — Vaccine Vesicles — Rodent Ulcer — Solid (Edema, 
or Elephantiasis Lymphangioides — Plexiform Neuroma — 
Lymphoma — Epithelioma, Sarcoma, Adenoma, and Lupus — 
Clonic Cramp of the Orbicularis Muscle — Blepharospasm — 
Ptosis — Operations for its Cure — Lagophthalmos — Sym- 
blepharon — Blepharophimosis — Canthoplastic Operation — 
Distichiasis and Trichiasis — Operations for their Cure — 
Entropium— Spastic Entropium — Senile Entropium — Opera- 
tions for its Cure — Ectropium — Operations for its Cure — The 
Restoration of an Eyelid — Ankyloblepharon — Injuries — Ecchy- 
mosis — Epicanthus — Congenital Coloboma. .... 276 



CHAPTER IX. 

DISEASES OF THE LACRIMAL APPARATUS. 

Malposition of the Punctum Lacrimale — Stenosis, and Occlusion of 
the Punctum Lacrimale — Obstruction of the Canaliculus — 
Stricture of the Nasal Duct — Blennorrhoea of the Lacrimal 
Sac — Obliteration and Extirpation of the Lacrimal Sac — Acute 
Dacryocystitis — Dacryoadenitis — Tumours of the Lacrimal 
Gland — Cysts of the Lacrimal Gland — Symmetrical Chronic 
Swelling of the Lacrimal and Salivary Glands — Extirpation 
of the Lacrimal Gland 320 



CHAPTER X. 

DISEASES OF THE SCLEROTIC. 

Inflammation of the Sclerotic— Periodic Transient Episcleritis, 
or Hot Eye — Episcleritis— Deep Scleritis— Syphilitic Gumma 
of the Sclerotic— Tumours of the Sclerotic— Pigment Spots 
— Injuries of the Sclerotic . . 338 



CONTENTS. 



xiii 



CHAPTER XI. 

DISEASES OF THE UVEAL TRACT. 

PAGE 

Tritis — Symptoms — Syphilitic — Rheumatic — Gonorrhceal — Prog- 
nosis — Causes — Treatment . 347 

Cyclitds . .363 

Chorioiditis — Disseminated — Syphilitic — Central Senile Guttate — 

Central — Purulent . 367 

Sympathetic Ophthalmitis, and Sympathetic Irritation— Intro- 
ductory — Sympathetic Irritation — Sympathetic Ophthalmitis 
— Diagnosis — Prognosis — Treatment — Prophylactic, Thera- 
peutic, and Optical Operations used in Sympathetic Ophthal- 
mitis — Pathogenesis — Pathology 372 

Injuries of the Iris — Punctured Wounds — Foreign Bodies — Irido- 
dialysis — Retroflexion — Rupture — Dehiscence — Traumatic 
Aniridia — Traumatic Mydriasis 393 

Injuries of the Ciliary Body — Punctured Wounds — -Foreign Bodies 397 

Injuries of the Chorioid — Foreign Bodies — Incised Wounds — 

Rupture— Extravasation of Blood 398 

New Growths of the Iris — Cysts — Granuloma — -Tubercle — Sarcoma 

— Ophthalmia Nodosa 399 

New Growths of the Ciliary Body — Sarcoma — Myosarcoma — Car- 
cinoma ..... 401 

New Growths of the Chorioid — Sclerotic Transilluminator — Sar- 
coma — Carcinoma — Tubercle— Sarcoma Carcinomatosum — 
Myosarcoma — Osteo-Sarcoma ...... 401 

Other Diseases of the Chorioid— Posterior Staphyloma — Detach- 
ment — Central Senile Areolar Atrophy 40G 

Malformations of the Iris ........ 408 

Malformations of the Chorioid 410 

Operations on the Iris 411 



CHAPTER XII. 

TIIK PUPIL. 

The Size of the Pupil in Health — Contraction of the Pupil — 
The Light Reflex — The Accommodation Synkinesis — Dilata- 
tion of the Pupil— The Sensory Reflex — The Cerebral Syn- 
kinesis 415 

Action of the Mydriatics and Myotics on the Pupil . . . 418 
Tabular Arrangement of Mydriatics, Myotics, and Anesthetics . -120 



xiv 



CONTENTS, 



CHAPTER XIII. 

GLAUCOMA. 

I'AOE 

Primary Glaucoma — Chronic, or Non-Inflammatory, Glaucoma — 
Acute, or Inflammatory, Glaucoma — Glaucoma Fulminans — 

Subacute Glaucoma — Etiology — Pathology — Treatment . . 424 

Secondary Glaucoma — Hemorrhagic Glaucoma . . . 446 

Congenital Hydrophthalmos 448 



CHAPTER XIV. 

DISEASES OF THE CRYSTALLINE LENS. 



Complete Cataracts — Senile Cataract— Progress, Pathogenesis, and 

Etiology — Treatment 449 

Complete Cataract of Young People — Diabetic Cataract — Complete 

Congenital Cataract — Black Cataract ... . 457 

Partial Cataracts — Central Cataract— Zonular, or Lamellar, 
Cataract — Anterior Polar, or Pyramidal, Cataract — Fusiform, 

or Spindle-Shaped, Cataract 458 

Secondary Cataract — Posterior Polar Cataract — Total Secondary 

Cataract 461 

Capsular Cataract 462 

Traumatic Cataract .......... 463 

Operations for Cataract — Extraction of Cataract — Linear Ex- 
traction — The Three Millimetre Flap Operation — Cataract 
Extraction without Iridectomy — Extraction in the Capsule . 465 
Discission . .......... 488 

Dislocation of the Crystalline Lens— Lenticonus— Aphakia . . 490 



CHAPTER XV. 

DISEASES OP THE VITREOUS HUMOUR. 

Purulent Inflammation — Other Inflammatory Affections — Hemor- 
rhage— Opacities — Muscas Volitantes— Fluidity (Synchysis)— 
Bynchysis Scintillans— Foreign Bodies in the Vitreous Humour 
and Interior of the Eye in General— Use of Kontgen Kays in 
Detecting Foreign Bodies— The Sideroscope— Kemoval of 
Foreign Bodies— The Magnet— Cysticercus— Blood Vessels- 
Persistent Hyaloid Artery 



CONTENTS. 



XV 



CHAPTER XVI. 

DISEASES OF THE RETINA. 

PAGE 

Alterations in Vascularity — Hyperemia — Anaemia. . . . 511 

Retinitis— Syphilitic — Hsemorrhagic — Albuminuric — Diabetic — 
Leucsemic — Development of Connective Tissue, or Retinitis 
Proliferans — Retinitis Circinata — Purulent Retinitis . . 512 

Atrophy of the Retina — Retinitis Pigmentosa — Punctata Albescens 

— Gyrate Atrophy of the Retina and Chorioid .... 520 

Diseases of the Retinal Vessels — Apoplexy of the Retina — Em- 
bolism of the Central Artery — Thrombosis of the Retinal 
Artery — -Thrombosis of the Retinal Vein — Sclerosis of the 
Retinal Vessels (Perivasculitis) — Quinine Amaurosis — Amau- 
rosis from Filix Mas . .• 523 

Injury of the Retina by Strong Light — Sunlight — Snow-Blindness 



—Effects of Electric Light on the Eyes 529 

Tumour of the Retina — Glioma 531 

Parasitic Disease of the Retina — Cysticercus 533 

Detachment of the Retina 533 

Traumatic Affections of the Retina — Traumatic Anaesthesia — ■ 
Commotio Retinas, or Traumatic (Edema of the Retina — 

' Holes' at the Macula Lutea 538 



CHAPTER XVII. 

DISEASES OF THE OPTIC NERVE. 

Optic Neuritis (Papillitis), due to : Cerebral Tumours — Tubercular 
Meningitis — Hydrocephalus — Tumours of the Orbit — In- 
flammatory J'rocesses in the Orbit — Exposure to Cold — 
Suppression of Menstruation — Chlorosis — Syphilis — 
Rheumatism — Lead- Poisoning — Peripheral Neuritis — Multiple 
Sclerosis — Tabes Dorsalis — Acute Myelitis — and to Hereditary 

and Congenital Predisposition 540 

Retro- Ocular Neuritis — Toxic Amblyopia, or Central Scotoma . 547 
Atrophy of the Optic Nerve, due to : — Optic Neuritis— Pressure — 
Embolism of the Central Artery of the Retina — Syphilitic 
Retinitis, Retinitis Pigmentosa, Chorioido-retinitis, and to 
DiaeaM of the Spinal Cord (Spinal Amaurosis)— Optic Atrophy 
as a purely Local Disease 551 



xvi CONTENTS. 

RAGE 



Tumours of the Optic Nerve — Hyaline Outgrowths — Injuries of 

the Optic Nerve 554 

Amblyopia clue to Hemorrhages from the Stomach, Bowels, or 

Uterus — Glycosuric Amblyopia 554 



CHAPTER XVIII. 

THE ORBITAL MUSCLES AND THEIR DERANGEMENTS. 

Normal Action of the Orbital Muscles — Inclination of the Vertical 
Meridian in the Several Principal Positions— Muscles called 
into Action in the Several Principal Positions — Subjective and 
Objective Localisation — -The Field of Fixation . . . 558 

Strabismus — Latent Strabismus, or . Heterophoria — Binocular 

Vision and Sense of Fusion — Diplopia 5G4 

Paralyses of the Orbital Muscles — General Symptoms — Paralysis 
of the External Bectus — Paralysis of the Superior Oblique — 
Paralysis of the Internal Bectus, Superior Bectus, Inferior 
Oblique, and Levator Palpebral — Mnemonic Diagrams — Oph- 
thalmoplegic Migraine — Ophthalmoplegia Externa, or Nuclear 
Paralysis — Fascicular Paralyses — Myasthenia Gravis — Cere- 
bral Paralysis of Orbital Muscles — The Localising Value of 
Paralyses of Orbital Muscles in Cerebral Disease — Congenital 
Defects of Motion . . .569 

Convergent Concomitant Strabismus — Causes — Single Vision in — 
Amblyopia of Squinting Eye — Clinical Varieties of — Measure- 
ment of — Mobility of Eye in — Treatment — Optical Treat- 
ment — OrthopticTreatment — Operative Treatment — Tenotomy 
— Advancement of External Bectus — Dangers of the Strabismus 



Operation — Treatment subsequent to Operation . . . G04 

Divergent Concomitant Strabismus 629 

Latent Deviations (Heterophoria) — Tests for Latent Deviations — 
Symptoms — Treatment — Latent Torsion — Insufficiency of 

Convergence . . . 630 

Nystagmus 639 



CHAPTER XIX. 

DISEASES OF THE ORBIT. 

Orbital Cellulitis— Tenonitis — Periostitis of the Orbit, — Caries of 
the Orbit — Injuries of the Orbit — Enophthalmos— Orbital 
Tumours — Hernia Cerebri— Cysts — Solid Tumours — Sym- 
metrical Tumours — Pulsating Exophthalmos — Intermit tent 



CONTENTS. xvii 

PAGE 

Exophthalmos— Tumours of the Optic Nerve — Implication 
of Neighbouring Cavities— Shrinking of the Conjunctiva — 
Temporary Resection of the Outer Wall of the Orbit- 
Exophthalmic Goitre 642 



CHAPTER XX. 

PART I. 

OCULAR DISEASES AND SYMPTOMS LIABLE TO ACCOMPANY FOCAL 
DISEASE OF THE BRAIN. 

Hemianopsia — Arrangament of the Cortical Visual Centres, their 
Relations to the Retina, and the Course of the Optic Fibres 
between these Two Points — Localisation of the Lesion in 
Hemianopsia — Alexia, or Word-Blindness — Visual Aphasia — 
Dyslexia — Amnestic Colour-Blindness — Visual Hallucinations 
— Mind-Blindness, or Optic Amnesia ...... 676 

PART 11. 

OCULAR DISEASES AND SYMPTOMS LIABLE TO ACCOMPANY CERTAIN 
DIFFUSE ORGANIC DISEASES OF THE BRA1JS. 

Disseminated Sclerosis of the Brain and Spinal Cord — Diffuse 
Sclerosis of the Brain — General Paralysis of the Insane — 
Amaurotic Family Idiocy — Meningitis — Traumatic Meningitis 
— Hydrocephalus — Infantile Paralysis — Paralysis Agitans — 
Encephalopathia Saturnia — Epilepsy — Chorea .... 690 

PART III. 

OCULAR DISEASES AND SYMPTOMS LIABLE TO ACCOMPANY CERTAIN 
DISEASES AND INJURIES OF THE SPINAL CORD. 

Tabes Dorsalis — Hereditary Ataxy— Myelitis— Syringomyelia and 
Morvan's Disease — Myotonia Congenita — Acute Ascending 
Paralysis — Injuries of the Spinal Cord . ... (59'J 

PART IV. 

STEBVO08 AMBLYOPIA, OR NERVOUS ASTHENOPIA. 

Nervons Amblyopia in Neurasthenia — Nervous Amblyopia in 

Hysteria — Nervous Amblyopia in Traumatic Neurosis . . 703 

b 



xviii 



CONTENTS. 



PART V. 

VAK10US FORMS OF AMBLYOPIA. 

PAOE 

Transitory Hemianopsia, or Scintillating Scotoma — Congenital 
Amblyopia — Keflex Amblyopia — Night-Blindness — Urajmic 
Amblyopia — Pretended Amaurosis — Erythropsia . . 711 

APPENDIX L 
Holmgren's Method for Testing the Colour-Sense .... 71!) 

APPENDIX II. 

Regulations as to Defects of Vision which Disqualify Candidates 
for Admission into the Civil, Naval, and Military Government 
Services, the Royal Irish Constabulary, and the Mercantile 
Marine 722 

Index 727 



TO THE STUDENT. 

The student may at first omit the portions printed in small 
type, and those marked with an asterisk, including the whole 
of chapter xx. With these exceptions he should carefully 
read chapters i., ii., iii., and iv., immediately on joining 
the ophthalmic hospital or department. 



DISEASES OF THE EYE. 



CHAPTER I. 

ELEMENTARY OPTICS. 

§1. The light from a luminous point travels in all directions in 
diverging straight lines which are called rays. The angle between 
the outermost rays which pass through an aperture (A. B, Fig. 1), or 
fall on a given surface, is the measure of the divergence of the rays. 
This divergence diminishes as the distance of the luminous point, 
from the surface on which the light falls, increases (Fig. 1), until it 
finally becomes so small that the ravs mav be considered to be 
parallel. In a strict 
mathematical sense, 
rays can only be 
parallel when the 
luminous point from 
which they come is at 
an infinite distance ; 
but, in ophthalmo- 
logics! practice, rays 
proceeding from any 
point at a distance 
of 6 metres, or more, 
from the eye may be 
regarded as parallel 
when they reach the 
pupil. Under natural conditions, rays entering the eye are either 
divergent (objects nearer the pupil than 6 m.) or parallel ; but they 
are never convergent, unless rendered so by artificial means (lenses, 
mirrors). 

§2. When light falls on an opaque object, some of the rays are 
absorbed, some are reflected in an irregular or diffuse manner, render- 
ing the object visible, while others are regularly reflected according 
to the amount of polish on the surface of the object, but none pass 
through it. When the object is transparent, the majority of the rays 
pa.'s through, but are bent or refracted. 

1 



E 


r"^rT 


s 


1 


E 


\ , — 1 


m 


B 



Fig. 1. The rays fromJD, which is further 
from A B than C, have a smaller angle of ] 
divergence. The parallel rays, E E, are sup- 
posed to come from a point infinitely distant. 



2 



DISEASES OF THE EYE. 



[CHAP. I. 



§3. Refraction, then, is the deviation which a ray of light undergoes 
when it passes from one homogeneous transparent medium into 
another of different density. The only rays which arc not refracted 
are those perpendicular to the surface (A B, Fig. 2). All others are 
deviated towards the perpendicular when passing from a rarer into 
a denser medium, and away from the perpendicular when travelling 
in the opposite direction. In Fig. 2 the incident ray, I H, travelling 

from the rarer medium (air) into 
the denser medium (glass), is 
bent towards the perpendicular, 
P, in the direction H R, and 
would continue in this path as 
long as it remained in the denser 
medium; i is the angle of in- 
cidence and t the angle of re- 
fraction. If the ray R H were 
to pass back in the opposite 
direction from the glass into air, 
it would be deviated away from 
the perpendicular, in the direc- 
tion H I. The path of the ray, 
therefore, is the same in eithtr 
direction. 

§4. Index of Refraction The 

more dense a medium is, the greater is its refractive power. 
The relative refractive power of a given substance is called the 
index of refraction of the substance, air being generally taken as 
the unit. A medium, therefore, having a greater density than air 
will have, as index, a number greater than unity; the index of 
crown glass, for instance, is 1-5. The cornea and the vitreous 
humour have the same index as water, namely 1-33, while that 
of the crystalline lens, as a whole, is 143. The refractive power 
depends on the difference between the indices of the t wo media ; for 
example, in the eye the cornea has a greater effect than the lens, 
although it has a lower refractive index than the latter, because the 
difference between air and the cornea is greater than that between 
the media (aqueous and vitreous) and the lens which lies in them, 

§5. Plane Parallel Surfaces (Plane Glass) bounding a transparent 
medium cause merely a lateral displacement of the rays without 
changing their direction, if. the first and last media are the same. 
In Fig. 2, C D F 0 may be taken to represent a piece of lilass with 
parallel sides C D and F (!, with air on each side. When the emergent 
ray, R E, passes out again into the air it is refracted away from the 
perpendicular, I", arid as the angles i and r' are equal, and the 
perpendiculars V and 1" are parallel, the ray E R is parallel to its 



A 


< * 


I 


\ 1 

\ v 'G 


t 

i 


trX \ 
! X N 
j, E 



FIG. 2. — Refraction at a plane 
surface. The surfaces C D and F G 
being parallel, the emergent R E is 
parallel to the incident raj' I H. 



CHAP. I.] 



EL EM EXT A R Y OPTICS. 



3 



original path I H, and suffers only a lateral displacement, which 
increases with the thickness of the plate. But the relative direction 
of the rays is not changed ; they retain the parallelism, divergence, 
or convergence, which they possessed before their passage through the 
plate ; hence no images are formed by plane glass, and objects seen 
through it are unaltered in size or shape. 



Fig. 



The 




Prisms. 

§6. Prisms are refractive media limited by plane sur- 
faces which are inclined at an angle, as in 
thin edge is called the Apex, a 
is the Refracting Angle, while 
the thick part opposite the 
apex is the base. In passing 
through a prism a ray of light 
undergoes a double refraction 
towards the base. The ray 
O is deflected towards the per- 
pendicular on entering the 
prism, and away from it on 
passing into the air at the 
side B A, the deviation being 
towards the base in each case. 

An object seen through a prism seems 
to be displaced toivards the apex ; for 
example, an eye placed at R receives 
the ray E R coming from 0, and 
imagines it to beat 0' in the prolonga- 
tion of R E. The deviation which the 
ray O has undergone is shown by the 
angle d (angle of deviation). In prisms 
made of crown glass, with an index 
of refraction of 1-5, the angle of de- 
viation is equal to half the angle of 
the prisms. Fig. 4 shows that, ns in 
plane glass, the relation of the rays to each other arc 
unaltered in their passage through a prism. 



Fig. 3. — Refraction by a prism. 
The rays from 0 are displaced 
towards the base, but 0 appears 
to an observer at R to be dis- 
placed towards the apex. 




Fig. 4 — Showing paral- 
lelism or divergence of 
rays unaltered by their 
passage through a prism. 



1 



DISEASES OF THE EYE. 



[chap. I. 




§7. Numbering of Prisms.— Prisms are numbered ac- 
cording to the size of the refracting angle (a, Fig. 3), which 
is expressed in degrees ; we speak of prisms of 1°, 2°, etc. 

This method of numeration is not quite accurate, because the 
deviation depends, not only on the angle of the prism, but also on 
the refractive index of the glass composing it ; hence, two prisms 

having the same number will not produce 
the same amount of deviation, or bo of 
the same strength, if the kinds of glass 
of which they are made have different 
refractive powers. It has, therefore, been 
proposed to number them according to the 
angle of deviation {d, Fig. 3), expressed 
C ■]_< either in Centrads or in Prism-Dioptres, a 
Fig. 5.— One centrad = centrac j be i ng a deviation {d, Fig. 5), the 
A T arc (C T) of which is of the radius, 
One prism dioptre ^- . while ; n the p r i sm _dioptre it is the tangent 

(A T) which is the of the radius 
(Fig. 5). The three methods are, however, equivalent for all practical 
purposes. The simplest plan would be to indicate the deviation, and 
not the angle of the prism, in degrees. 

§8. Recognition of a Prism and the Base-apex Line. - 

Prisms used in ophthalmic practice are usually cut round 
for convenience of placing in trial frames, but the thick 
base and thin apex are sufficient to distinguish them from 
lenses or plane glass. In weak prisms this is not so evident, 
but they can always be recognised by the displacement 
which they cause when an object is seen through them, 
by quickly putting the prism up before one eye, the other 
being closed, or if the prism be rotated before the eye, an 
object seen through it will be observed to move in a circle, 
following the displacement of the apex. Figs. 6 & 7 show 
a simple method of detecting the displacement, and at the 
same time of ascertaining the exact position of the apex 
and base. The prism is held at a short distance from the 
eye opposite two crossed lines, vertical and horizontal 
(the bars of a window-sash, say), so that they can be seen 
outside the glass as well as through it. Tf, as in Fig. 6, 



CHAP. I.] 



ELEMENTARY OPTICS. 



5 



the apex and base, A, and B, are exactly horizontal, then 
the portion of the vertical line C D seen through the glass 



will alone be displaced towards the apex ; but if the prism 
be oblique both lines will be displaced as in Fig. 7. 

§9. Effect of a Prism on Binocular Vision.— When 

a prism is placed before one eye, both eyes being open, 
the immediate effect is to cause double vision or diplopia, 
which either persists, or is overcome by an effort of 
one of the orbital muscles. In fig. 8, the image of the 
object, 0, falls on the macula lutea, M, in the left eye (L), 
but instead of falling on the macula, M, in the right eye 
(R) it is displaced by the prism, towards the base of 
which it is refracted, to a point B on the retina, which 
is not physiologically identical with M in the left eye, 
and 0 now appears to the right eye to be at 0', in the 
prolongation of B P, and the patient sees two images, one 
with each eye. An unconscious effort is then made by 
the patient to bring the macula, M, into the position B. 



c 



c 



A 





D 

Fig. 7.— Prism held obliquely, 
both vertical and horizontal 
lines displaced. 



6 



DISEASES OF THE EYE. 



[chap. r. 



This is accomplished by the action of the Ext. Rectus (R E), 

and thus single vision is again obtained. If desired, 

by increasing the strength of the prism until the diplopia 

can no longer be overcome, the strength of the muscle, 

in this instance the Ext. 

Rectus, can be estimated. 

It will be observed also, 

that when, in order to 

correct the diplopia, the 

axis of the eye has moved 

into the position P B, the 

convergence of the eyes is 

diminished, and therefore 

the effort of the internal 

rectus muscle must to a 

certain extent be relieved. 

1.'.^, o -n- i t i j j From this it follows, that 

lUG. 8. — Binocular diplopia produced J - iv -"" ""^ iu j 

by a prism. the muscle towards the 

apex of the prism is 
brought into action, while the muscle towards the base is 
relieved. The rotatory prism, composed of two prisms of 
equal strength, in contact, and rotating in opposite direc- 
tions, is a useful instrument for measuring purposes, as by 
its aid values of from 0° up to the strength of both 
prisms combined can be obtained gradually. Maddoxs 
double prism is also very convenient for producing diplopia 
(see Latent Deviations, chap, xviii.). 

§10. Uses of Prisms.— 1. By the production of diplopia, 
prisms can be used, (a) to test the strength of muscles, 

(b) to detect latent deviations or insufficiencies of muscles, 

(c) to strengthen weak muscles by exercise, (d) to test 
binocular vision, (e) to detect feigned blindness of one 
eye. 2. For the purpose of correcting or measuring the 
diplopia in paralysis, or insufficiencies of orbital muscles. 

§11. Prescribing- of Prisms.— In practice prisms of 




CHAP. I.] 



ELEMEXTA i? Y OPTICS. 



7 



more than four degrees can rarely be 'worn by patients, 
owing chiefly to the weight and colour effects of higher 
numbers. The position of a prism placed before an eye 
is indicated by reference to its base, e.g., Pr. 3° base up, 
down, in, or out, as (he case may be. 



Lenses. 




§12. A lens is a portion of a transparent refracting 
medium bounded by two surfaces, one or both of which are 
curved. It may be spherical, or cylindrical, or it may be 
compound, that is to say spherical on one surface and 
cylindrical on the other. 

§13. Spherical Lenses are bounded by spherical surfaces, 
and therefore their action is the 
same in all meridians ; they are 
either convex or concave. Convex 
spherical lenses may be regarded 
as composed of prisms with their 

bases together (fig. 9) and are 

. , ' Fig. 9.— Convergent 

thicker m the centre. They con- effect of a convex or + lens, 
verge parallel rays of light, and F, principal focus, 
bring them to a point or focus. 

Concave lenses, on the other hand, are like prisms with 

their apices together (Fig- 10), 
and are thinner in the centre. 
They cause parallel rays of light 
to diverge. Convex lenses are 
positive, and are indicated by the 
sign + (plus). Concave lenses 
are negative, and marked with 
the sign — (minus). The former 
placed in front of the eye add 
to its refractive power, the latter diminish it. Fig. 1 1 
shows the different kinds of spherical lenses in use. In 




Fig. 10.— Divergent effect 
of a concave or - lens. F, 
principal focns. 



8 



DISEASES OF TEE EYE. 



[chap. I 



the convex meniscus, the convex surface has a shorter 
radius of curvature than the concave ; whereas in the 
concave meniscus, the concave surface has the smaller 
curve. Meniscus lenses are also called periscopic {irepi, 



Gonvexor+. Concaveor — 



Plano-convex 



u- convex 



IXI 



Plano-concave 



Biconcave 



Concave meniscus, 
(periscopic lens J 



Fig. 11 . — Different forms of spherical lenses. 

around ; crKoirelv, to look), because (with the concave surface 
towards the eye) they produce less distortion towards 
their edges, and consequently permit a greater excursion 
of the eye. 

§14. Axes Of Spherical Lenses.— The Principal Axis 
of a spherical lens (P A, Fig. 12) is the line joining the 

centres of curvature of the sur- 
faces, and the point 0 in the centre 
of the lenses on the principal axis 
is known as the Optical Centre. 
Any ray passing through the optical 
centre, except along the principal 
axis, is called a Secondary Axis, 
and it emerges parallel to i!s 
original direction (N E is parallel 
to S S'). In thin lenses the slight 
displacement may be neglected, and the secondary axes may 
be considered to pass through the optical centre without 
any deviation. These statements apply to both convex and 
concave lenses. 




FIG. 12.— Primary and 
secondary axes of a lens. 



CHAP. I.] 



ELEMENTARY OPTICS. 



9 



a 1 




U | 

A 




u 




0 \ 




Focal length 



FlG. 13. — Principal focus 
(P F) and focal length of a lens. 



§15. Principal Focus of Convex Spherical Lenses.— 

The point to which parallel rays of light converge after 
passage through a convex lens 
is called the Principal Focus 
of the lens, and the distance 
of this point from the lens is 
the focal length (Fig. 13). Rays 
of light diverging from the prin- 
cipal focus pass out parallel on 
the other side of the lens. 
Rays (« c, Fig. 13,) parallel 
to the principal axis, have their focus on this axis, 
while those which are parallel to a secondary axis, (A S, 

Fig. 14,) are brought to a 
focus on the secondary axis 
at a point (S), where it cuts 
the perpendicular line passing 
through the principal focus 
(principal focal plane), 
stronger the lens the 
the rays are refracted, 
therefore the shorter is 
focal length (Fig. 15). 

§16. Conjugate Foci 

foci which are so related that 
them pass to the other and vice versa. 




Fig. 14. — Kays A andB, paral- 
lel to the secondary axis A S, 
unite in the focal plane F P atS. 



The 
more 
and 
the 

are 



rays from one of 
For instance, the conjugate focus 
of parallel rays (or infinity) is 
the principal focus, and the latter 
is again the conjugate focus of 
infinity. 

§17. Real, or Positive Con- 
jugate Focus of a Convex 

Lens. —We have now to consider 
what happens to rays which diverge from points on either 











-4/ 





Fio. 15. — Tbe stronger 
lens (2) has a shorter 
focus, K 2. 



DISEASES OF THE EYE. 



[CHAI\ I. 



side of the principal focus ; namely, points further from, or 
nearer to, the lens than the principal focus. In Fig. 16 the 
rays from the point 1 further from the lens than the principal 
focus F, converge to 1', beyond F, on the other side of the lens, 
and form an image there, which is real and can be received 
on a screen. When the point from which the rays diverge 
approaches nearer to F, say at 2, then the conjugate focus 




Fig. — Real, or positive, conjugate foci of a convex lens. 



moves further away to 2', until, when the point reaches 
the principal focus F, the conjugate focus has moved away 
to infinity, and the rays are parallel. It will be noticed 
that in this case the conjugate foci are on opposite sides 
. of the lens, but that they move in the same direction. 

§18. Virtual, or Negative, Focus of a Convex Lens. — 
When rays proceed from a point nearer to the lens than the 




Fig. 17.— Virtual, or negative, conjugate foci of a convex lens. 

principal focus F, the angle of divergence being greater than 
at F, the lens is not sufficiently strong even to render them 
parallel, and they therefore continue to diverge after their 
passage through the lens, but not so much as before. In 
Fig. 17, the rays coming from P internal to the principal 



CHAP. I.] 



ELEMENTARY OPTICS. 



11 



focus, F, are rendered by their passage through the lens, L, 
less divergent than before ; but, being divergent, they can- 
not come to a focus. To an observer at C, however, looking 
through the lens, the rays A and B would seem to come 
from a point P', in the direction of their prolongation. P' 
is the conjugate focus of P, but it is virtual as opposed to 
real, and is negative, or on the same side of the lens as P. 
If we consider the rays as travelling in the opposite direc- 
tion, A and B with a convergence towards P' will be 
focussed at P. 

§19. Foci of Concave Spherical Lenses. — A concave 

lens renders parallel rays divergent. In Fig. 18, rays A and 
B, parallel to the principal 



axis P X, diverge as if they 
came from F, which is the 
principal focus of the lens. 
Pays from a near point will 
be rendered still more di- 



A 


•A > p£tf~ 






X 


B i — 



vergent, and will appear to Fig. 18. — Principal focus of a 
proceed from a point still concave lens, 

closer to the lens than the 

principal focus, F ; but, in all cases, the conjugate focus 
will be apparent or virtual, and also negative, or on the 
same side of the lens as the point of light. Convergent rays 
are rendered parallel by a concave lens, if they converge 
towards the principal focus on the other side of the lens, 
and divergent if the point towards which they converge is 
further from the lens than the principal focus. They still 
remain convergent, but less so than before, if the point 
towards which they converge is closer to the lens than the 
principal focus. 

§ 20. Images formed by Spherical Lenses consist of foci, each of 
which corresponds to a point in the object, and of which it is the 
conjugate focus. The image is real when the rays forming it actually 
meet and can be received on a screen ; it is virtual when it does not in 



12 



DISEASES OF THE EYE. 



[chap, i. 



reality exist, but is formed by the imaginary backward prolongation of 
the rays, and can only be seen by looking through the lens. 

§21. Method of finding the Position and Size of an Image formed by 
a Spherical Lens.— In order to find the position of the image of a 
point, say of 0, Fig. 19, formed by a lens, first draw the secondary 
axis 0 I, which passes through the optical centre without deviation. 
The image will be formed on this axis at a point where the other rays 





A 


\F2 







Fig. 19. — Image of a given point 0 formed by a convex lens. 



proceeding from 0 intersect it. Two other rays (the paths of which are 
known) can be utilised ; 0 A parallel to the principal axis will pass 
through the principal focus F„, and the image of O will be at I, where 
A I meets 0 I, or I can be found by means of the ray 0 C, which passes 
through the principal focus, F|, and therefore becomes parallel to the 
principal axis, taking the direction C I. In the following examples, 
the ray O A only will be used. 
§ 22. Real Inverted Image formed by a Convex Lens. — When[an - ob- 



C D 



A E 



Fig. 20.— Real inverted image formed by a convex lens when the 
object is further from the lens than the principal focus. 



ject is further from the lens than the principal focus, an inverted 
image is formed, as in Fig. 20, and the image is equal to the object 
A C, and at the same distance from the lens, if the object be at twice 
the focal distance from the lens. The image is larger if the object be 



CHAP. I.] 



ELEMENT A R Y OPTICS. 



L3 



closer than 2F (e d is the image of D E), and smaller if it be further 
than 2F (D E is the image if e d be the object). The closer the object 
is to the principal focus, the larger the image. It is in this way that 
the image is produced in the indirect method of ophthalmoscopy. 

§23. Virtual, Erect, and Magnified Image formed by a Convex Lens.— 
When the object, C D (Fig. 21) is closer to the lens than the principal 




Fig. 21. — Virtual erect and magnified image formed by a convex 
lens, when the object is closer to the lens than the principal focus. 

focus F,, an erect, magnified virtual image, e d, can be seen on looking 
at the object through the lens. As the object approaches the lens, say 
to N P, the image, np, becomes smaller ; in other words, the virtual, like 
the real inverted image, increases in size the nearer the object is to F,. 
It is in this way that a convex lens is used as a magnifying glass. 
§ 24. Images formed by Conoave Lenses are always erect, virtual, and 




Fio. 22. — Virtual erect and diminished image formed by a 
concave lens. 

diminished. The nearer the object is to the lens the larger the image. 
In Fig. 22 the point c or image of C is found at the intersection of S R 
( prolonged back to the principal focus, F) with the secondary axis C 0 N , 
and d e is the image of D E. 



DISEASES OF THE EYE. 



[chap. i. 



§25. Cylindrical Lenses. — A lead pencil is a good ex- 
ample of a cylinder, the lead running down the centre 
being its axis. Any lines on the surface, parallel to the 
axis, are straight lines, whereas sections at right angles to 
the axis are always curved. If a slice were taken oft* the 
surface of the pencil, in the direction of its length or axis, 
and a round piece cut out of it, it would represent a convex 
cylindrical lens. A cast of the surface of the pencil would 
form a concave cylinder. Cylinders only act in the direction 
of their curvature ; that is to say, at right angles to the 



Axis 



Horizontal 
Plane 



Vertical 




Fig. 23.- 



Plane 



-Refraction through a convex cylinder. F principal focus, 
which is really a line parallel to the axis. 



axis. A cylinder has no effect in the direction of its axis. 
Eays entering in the plane of the axis are not refracted 
(Fig. 23, a), and rays entering in any plane parallel to the axis 
(Fig. 23, b) are merely bent towards the axis, but suffer no 
deviation in the direction of the axis (that is to say, vertically 
in Fig. 23). On the other hand rays in a plane at right 
angles to the axis, meeting the curved surface, are made to con- 
verge or diverge, according as the cylinder is convex or concave. 
(Horizontal plane in Figs. 23 and 24.) The focus of a cylinder 
therefore is a line parallel to the axis, and no image is formed. 



CHAP. I.] 



ELEMENTARY OPTICS. 



IS 



The position of a cylinder placed before the eye, is in- 
dicated by the degree of inclination of its axis to the vertical 
or horizontal. The axis of the cylindrical lenses used in 




Fig. 24. — Refraction through a concave cylinder. 



trial-cases is indicated by two slight scratches at the edge, 
or by two muffed portions parallel to the axis. 

§26. Numbering 1 of Lenses. — The lenses in trial-cases 
and in spectacles are numbered according to the metric 
system. 

A lens of one metre focal length is adopted as the 
Dioptric Unit or unit of refractive power, and is called 
a Dioptre (1 D). The greater the strength or refractive 
power of a lens the higher will be its number, and the 
shorter will be its focal length (Fig. 15). Lenses of 2 D 
and 4 D are twice and four times as strong, respectively, 
as a lens of 1 D, and their focal lengths will be inversely, 
| and % of the focal length of the 1 D lens, that is to say 
-y and " ( ", Or expressed in centimetres (1 metre = 100 centi- 
metres), = 50 cm., and ^ = 25 cm. 

If, Hereford, it be required to ascertain the focal length 
of a given lens, 100 must be divided by the dioptric number 



16 



DISEASES OF THE EYE. 



[chap. t. 



of the lens, and the answer will give the focal length in 
centimetres. For example, the focal length of a lens of 5 D 
is loo _ 20 cm. 

If the focal length of the lens be known, and it be 
desired to ascertain its dioptric number, we find it by 
dividing 100 cm. by the focal length. For example, if the 
focal length be 33 cm., then Yir = 3 D. 

Lenses of less than 1 D have of course decimal fractions 
for their numbers— e.g., 0-75, 0-5, and 0'25. The focal length 
of 0-5 D is = 200 cm. = 2 metres. Cylindrical lenses 
are numbered in the same way as sphericals. The strength 
of two lenses in contact is practically equal to the sum of 
their numbers, if of the same kind, and to the difference 
of their numbers if of the opposite kind — e.g., + 4 D lens 
combined with —ID lens equals a + lens of 3 D. 

§27. Recognition of Spherical Lenses.— If a spherical 




FlG. 25. — Apparent, movement, 
in the opposite direction, pro- 

• duced by displacement of a 
convex lens. In position 2, 
O B is deviated towards the 
base of the prism to D, and 0 
is seen at 0' (Chap. I. § 6.) 




FlG. 2(5. — Apparent movement, 
in same direction, produced 
by displacement of a concave 
lens. In position 2 the prism 
is base up, 0 B is deviated to 
D, and 0 seems to be at 0'. 



lens be moved before the eye, when looking at an object 
through it, the object will seem to move in the opposite 
direction in the case of a convex tens, and in the same 
direction, if the, lens be concave, This is due. to the 



CHAP. I.] 



ELEMENT A R Y OPTICS. 



17 



Axis 




Fig. 27. 



prismatic action of the lenses (Figs. 25 and 26), and occurs 
equally in all diameters. 

* §28. Recognition of Cylindrical Lenses and of the 

Position of the Axis. — Cylinders act in the manner de- 
scribed above for spherical lenses, but 
only in a direction at right angles to 
the axis. Further, if a cylinder be 
rotated while an object is viewed 
through it, it produces a distortion, 
when the axis is oblique with regard 
to the chief lines of the object. The 
effect is best seen if a rectangular object 
be selected, the angles of which arc 
then no longer right or equal. This 

is noticeable even when the cylinder is combined with a 
spherical lens. 

The simplest plan is to look at a vertical line through 

the glass, and if the axis of 
the cylinder be either vertical 
or horizontal, the portion of 
the line seen through the 
glass appears to be continuous 
with that outside it, whereas 
if the axis be oblique, as in 
Fig. 27, the portion seen 
through the lens becomes 
twisted into the position a 
b. Maddox's axis-finder, 
Fig. 28, is based on this prin- 
ciple. The spectacle frame 
is placed in a groove on the 
top of the instrument, and 
is held there, while both are tilted round until the line 
appears continuous as at A, Fig. 28; the pendulum, P, 
then indicates on the graduated arc the position of the 

2 




18 



DISEASES OF THE EYE. 



[chat, i 



axis, or the direction at right angles to it. The axis 
can also be found by the lens measurer (see below). 

* §29. To find the Number Of a Lens it is only necessary 
to neutralise it with a lens of the opposite kind taken from the 
trial-case. The two lenses are held in contact and moved 
together, while the apparent motion of an object as seen 
through them is noted, the lens which stops all movement 
giving the required number. Or it can be ascertained more 

rapidly by the Geneva lens measurer, 
Fig. 29. The three points a, b, c, the 
central one, b, of which is movable, 
are applied to the surface of the lens, 
and the corresponding number is 
indicated by the pointer on the 
dial. Both surfaces of the lens 
must of course be measured. The 
position of the axis of a cylinder 
is also easily found by this in- 
Fig. 29. — Lens measurer. strument. When the points are 

placed parallel to the axis the 
index stands at 0 (zero), showing that the surface is plane 
in that direction. 

* §30. To find the Optical Centre of a Lens is often a 

matter of practical importance. It can be found in the 
same way as is the base-apex line of a prism (Fig. 7). When 
both the crossed lines seen through the lens are continuous 
with the portions outside the lens, the optical centre is 
opposite the point of intersection of the lines. 

* §31. Decentration Of Lenses. — Normally, the distance 
between the optical centres of the lenses in spectacles should 
be the same as that between the optic axes of the eyes of 
the patient, otherwise a prismatic effect would be produced. 
Sometimes, however, such an effect is desirable, and then it 
can be brought about by decentration of the lenses ; which 
may be done in two ways, namely, by altering the distance 




CHAP. I.] 



ELEMENTARY OPTICS. 



19 




between the glasses by means of the frames, or by decentring 
the glass in its rim. The effect of the first method is 
shown in Fig. 30, from which figure, too, it is evident that, 
in order to produce the same effect, convex and concave 
lenses must be displaced in 
opposite directions. 

The second plan consists 
in cutting out the lens so 
that the optical centre is 
displaced with reference to 
the geometrical centre. By 
the geometrical centre we 
mean the central point of 
the piece of glass consti- 
tuting the lens. In round 
glasses it is of course equally 
distant from all parts of the 
circumference, and in oval 
glasses it is at the centre 
of the horizontal diameter 

of the glass. In lenses, as commonly made, the optical 
centre coincides with the geometrical centre. Fig. 31 
shows how a lens can be cut so that the optical centre 

will be decentred. A B is the lens 
as originally ground, and B C D is 
the portion which is cut out and 
fitted in the spectacle rim. If the 
whole of AB were used, the optical 
centre, O, would be the geometrical 
centre, but in the portion C B D 
the point G, midway between C D 
and B, would be the geometrical centre, while the optical 
centre, O, would be decentred. To obtain a prismatic effect 
of 1' a lens of 1 D requires to be decentred 1£ cm. 
The stronger the lens the greater is the prismatic effect 



Fig. 30.— Prismatic effect of de- 
celeration of lenses. A B and C D 
represent the visual axes. 



Fig. 31.— Decentration 
of a lens by cutting out 
a portion of it. 



20 



DISEASES OF THE EYE. 



[chap. i. 



produced by a given amount of decentration, so that a lens 
of 2 D need only be decentred half the distance of a lens 
of 1 D, in order to produce the same prismatic effect. 
Tables have been made giviDg the prismatic effect of 
lenses of different strength corresponding to the extent of 
the decentration in millimetres. 1 



See Maddox's work Opltthalmological Prisms. 



CHAPTER II. 



OPTICAL STRUCTURE AND FUNCTIONAL 
EXAMINATION OF THE EYE. 

Preliminary Note on the Clinical Examination of Eye 

Patients. 

In general medicine and surgery, the importance of 
systematic clinical methods is well recognised. System is 
even more necessary in the clinical study of diseases of 
the eye, where the objects to be examined are often so 
minute that they may readily escape observation, and the 
symptoms depending on derangement of the functions of the 
organ are sometimes such, that the patient may himself 
be unaware of them. 

Before examining the eye, a general observation of the 
patient should be made, whereby suggestive hints may be 
obtained for diagnosis. For example : the manner in 
which a patient enters a room may help to distinguish 
between an affection of the nervous apparatus of the eye and 
cataract, or his gait may suggest an affection associated with 
disease of the spinal cord. Again, a strumous appearance, 
enlarged glands, eczema, syphilitic eruptions, or the aspect 
due to hereditary syphilis afford information not to be 
disregarded. 

There are many obvious local conditions, which are 
liable to escape the attention of a student who is, as so 
many are inclined to be, too precipitate in beginning a close 
inspection of the eyeball itself ; for instance, the presence 
of slight strabismus, photophobia, or slight ptosis, or the 

21 



22 



DISEASES OF THE EYE. 



[CHAI*. II. 



sleepy appearance due to the heavy thickened lid in granular 
ophthalmia. These are mentioned merely to indicate the 
advantages which may be gained by taking a general view 
of the patient, and of his eyes, at a little distance, before 
proceeding to examine the latter more particularly. 

The examination of the eye may be divided into three 
parts, which are usually taken in the following order : 
1. Objective examination in daylight. 2. Subjective, or 
functional, examination. 3. Objective examination in the 
dark room. All these will be described in their appro- 
priate places in the following pages, and it is only 
necessary here to mention some of tbeir subdivisions. 
Under the first will come inspection (and palpation wben 
possible) of the orbit, eyelids, lacrimal passages, conjunctiva, 
cornea, anterior chamber, iris (its colour and structure, and 
the mobility, shape, and size of the pupil), anterior layers 
of the lens in the pupillary area, and testing tbe intraocular 
tension. The second will include tests for acuteness of 
vision, field of vision, accommodation, orbital muscles, colour 
vision, and light-sense. Finally, in the dark room the anterior 
parts of the eye, including the lens, and sometimes tbe 
anterior portion of the vitreous humour, are first examined 
by reflected light with oblique illumination, and then with a 
strong +lens in the ophthalmoscope. The details of the 
fundus are then observed with the ophthalmoscope, and the 
refraction is estimated if necessary. One should never omit 
to compare the affected eye with its fellow, if only one 
eye be diseased. 

It is not intended that all these methods of examination 
should be put into use, or considered even necessary, in 
every case ; but they should be borne in mind, if nothing is 
to escape attention. 

Optical Structure of the Eye.— The eye is a dark 
chamber lined by the uveal pigment, which prevents the 
rays of light from entering it, except through the transparent 



chap. II.] OPTICAL STRUCTURE OF THE EYE. 



23 





cf An- 




0 




v 



media and pupil. It possesses three refractive or dioptric 1 
media, limited by three convex surfaces. The dioptric 
media are the aqueous humour, the substance of the 
crystalline lens, and the vitreous humour. The convex 
surfaces are the anterior surface of the cornea, 2 and the 
anterior and posterior surfaces of the crystalline lens. 

By aid of this apparatus, which is called the dioptric 
system of the eye, distinct inverted images of external 
objects are formed on the retina. 

The refracting surfaces, which are practically spherical, 
are centred on the optic 
axis (0 P, Fig. 32), an 
imaginary line which, 
passing through the op- 
tical centre (#) of the 
eye, meets the retina 
at a point (P), the pos- 
terior principal focus, 
slightly to the inner 
side of the macula 
lutea (if). 

The optic axis of the eye is similar to the principal 
axis of a convex lens (see § 15, chap. i.). The optical centre 
.\', which is called the nodal point, is situated just in front 
of the posterior surface of the lens, and rays passing through 
it are not deviated in their path, being in fact secondary 
axes. V M is the visual line, which unites the object 
looked at with the macula lutea (M) and passes through the 
nodal point. 

The Line of Fixation (It V) joins the centre of rotation 
'/,'; of the eye with the point of fixation. The angle 0 It V 

1 The phenomena of refraction are sometimes referred to as 
Dioptrics, and those of reflection as Catoptrics. 

- The posterior surface of the cornea may be neglected, since it is 
parallel to the anterior surface and the index of refraction of the 
cornea is the same as that of the aqueous humour. 



FIG. 32.— 0 P, Optic axis ; V M, Visual 
line ; O R V, angle y ; R, centre of ro- 
tation ; JV, nodal point ; C, centre of 
cornea. 



24 



DISEASES OF THE EYE. 



[chap. II. 



formed at the centre of rotation, by the optic axis and the 
line of fixation, is called the angle 7. 

The line of fixation and the visual line so nearly coincide 
that in practice we regard them as identical ; and hence 
the angle 7 is practically the same as 0 N V. 

The angle k is the angle between the fixation line 
and a perpendicular line through the cornea, opposite the 
centre of the pupil. In practice it is the angle k which is 
measured. It is not equal to the angle 7, because the 
centre of the pupil is a little to the inner side of the centre 
of the cornea. 

In order to measure the angle k, the eye is placed at 
the perimeter as for an examination of its field of vision, 
that is to say, looking at the zero - point. A candle flame 
is then moved along the arc of the perimeter, until the 
corneal image of the light appears to the observer (whose 
eye is in a line with candle and image) to be in the centre of 
the pupil. The position of the flame at the perimeter 
then gives the angle k. The average size of the angle k 
is 5°. 

Eefraction. 

By the Eefraction of the Eye is meant, in a general 
sense, the faculty it has when at rest {i.e., without an effort 
of accommodation) of altering the direction of rays of light 
which pass into it, making parallel rays convergent, and 
divergent rays less divergent. But, as usually understood, 
it means the relation which the position of the retina bears 
to the principal focus of the dioptric system. 

In Normal Eefraction, or Emmetropia {efM^erpov, the 
standard ; &\\r, the eye), as it is termed, the retina lies 
at the posterior principal focus (fig. 33), and therefore 
parallel rays are brought to a focus on the layer of rods 
and cones of the retina, and form on it a distinct inverted 
image of the point or object from which they come. The 



chap. II.] OPTICAL STRUCTURE OF THE EYE. 



26 



emmetropic eye, in a state of rest, is thus adapted for 
distant objects, and its far point (punctum remotum) is 
at infinity. Conversely, if the retina be illuminated, the 
rays proceeding from any point on it will emerge from the 




Fig. 33. 



eye parallel. In the normal eye the posterior focal length 
of the dioptric system is 23 mm., and the average length 
of the eyeball including the sclei'otic is 24 mm. 



Accommodation. 

The eye can see near objects distinctly as well as distant 
objects, although the rays from any given point (a, Fig. 34) 




Fig. 34. 



of a near object reach the eye with a divergence so con- 
siderable, that they could not be brought to a focus on the 
retina by the unaided refraction, but would converge towards 
a point (their conjugate focus a) behind the retina, and would 
not form a distinct image on the latter, but merely a blurred 



20 



DISEASES OF THE EYE. 



[chap. II. 



image or circle of diffusion (at be). It is obvious, therefore, 
that an increase of refracting power in the eye is necessary, 
in order that near objects may be distinctly seen. It is 
this increase in the refracting power for the purpose of 
near vision which is called Accommodation. 

The Mechanism of Accommodation is as follows: — The 
ciliary muscle Fig. 35) contracts, thus drawing forward 
the chorioid and the ciliary processes, and relaxing the zonula 
of iZinn (2), which is attached to the latter. The lens (I), 




Fig. 35.— c, cornea ; a, anterior chamber ; I, lens ; v, vitreous humour ; 
i, iris ; z, zonula of Zinn ; m, ciliary muscle. 

which was flattened by the tension of the zonula, is now free 
to assume a more spherical shape, in response to its own 
elasticity. The posterior surface of the lens scarcely alters 
in shape, being fixed in the patellary fossa ; but the anterior 
surface becomes more convex, thus increasing its refracting 
power. Associated with the act of accommodation is a 
contraction of the pupil. The accompanying figure (Fig. 35) 
represents the] changes which take place in accommodation, 
the dotted lines indicating the latter state. 

Tscherning has shown that the increased curvature of 
the anterior surface of the lens occurs mainly in the centre 



chap, ii.] OPTICAL STRUCTURE OF TIIE EYE. 



27 



of that surface — iu other words, that in accommodation 
the anterior surface becomes somewhat conical, and not 
merely more spherical. He holds that this is due to a 
tightening, and not to a relaxation of the zonula. This 
theory has been vigorously combated by other observers, 
and its true value remains to be determined. 

Accommodation is always associated with contraction of 
the pupil and convergence of the optic axes. 

The Far Point and the Near Point.— It is possible 

for the eye, by changing the accommodation, to see objects 
accurately at every distance from its Far Point — i.e., its 
most distant point of distinct vision (Punctum Remotum, 
— P.), up to a point only a few centimetres from the eye, 
called the Near Point (Punctum Proximum, — P.). We 
can find the latter by directing the patient to look at a 
page printed in small type, and by bringing it slowly closer 
and closer to his eye, until a point is reached where he 
cannot distinguish the words and letters, which become 
blurred. A point very slightly more removed from the eye 
than this, where he can read distinctly, is the near point. 
Between the near point and the eye vision is indistincb, 
because no effort of the ciliary muscle can produce the amount 
of convexity of the lens required for so short a distance. 

* The Amplitude and Range of Accommodation.— 

This is the amount of accommodative effort of which the eye 
is capable — i.e., the effort it makes in order to adapt itself from 
its Far Point (R.) up to its Near Point(P-). The amplitude 
of accommodation (a), therefore, is equal to the difference 
between the refracting power of the eye when at rest (?•), 
and when its accommodation is exerted to the utmost (/>), as 
expressed by the formula a = p — r. It may be represented 
by that convex lens placed close in front of the eye, which 
would take the place of the increased convexity of the lens, 
or, in other words, which would give to rays coming from 
the nearest point of distinct vision a direction as if they 



2K 



DISEASES OF THE EYE. 



[chap. II. 



came from the far point. The number of this lens expresses 
the amplitude of accommodation in a given eye. 

For example : if, in an emmetropic eye (E, Fig. 36) the 
near point be situated at 20 cm., then a convex lens (L) of 20 
cm. focal length placed close to the eye (between that point and 
the eye) would give to rays coming from the near point a direc- 
tion as though they came from a distant object (i.e., would make 
them parallel), and this normally refracting eye would then 
be enabled by aid of its refraction alone to bring these rays 



20- Qri <C "~~-^^ 


G 


% 


^^^^^^ 


Fig. 36. 



to a focus on the retina. Making use of the above equation, 
we find in this case — since a focal length of 20 cm. represents 
a lens of 5 D — that a = 5 — r, but E, being situated at 

infinity (designated by the sign co), r = — =— = 0; 

therefore a = 5 — 0=5 D. 1 



1 It must be observed that R represents the distance of the Far Point 
from the eye, while r represents the refractive power which is added 
to the eye by accommodation, or by a lens, in order to adapt it for the 

distance R. Hence it is evident that r = ^, because the strength, 

or refractive power, of a lens is inversely as its focal length — e.g., a, lens 
of the strength of i D will have a focal length of J that of a lens of 1 D — 

i.c.j-E:— 10Q ^ cta - = o-25 cm. (see § 2G p. 15). Similarly, .?;=iand 
a =— ; V representing the distance of the Near Point, and A the 

A. 

focal length of the lens a which represents the Amplitude of 
Accommodation. 



chap. II.] OPTICAL STRUCTURE OF THE EYE. 



29 



The amplitude of accommodation {i.e., the number of 
the lens which would represent it) is the same in every 
kind of refraction, according to the age of the individual, 
but in emmetropia alone is a=p as above, because in it 
alone is r = 0. 

It is evident that, as the refractive power of the eye is 
increased during accommodation, the eye is rendered tem- 
porarily myopic as regards parallel rays (Fig. 37). 

Under the head of " Anomalies of Accommodation," 
chap, iii., will be found 
Donders' diagram 
representing the am- 
plitude of accommo- 
dation at different 
ages. 

The Range of Ac- 
commodation is the 
distance between the 
far point, E, and the 
near point, P. As will be seen later on, it is not always 
the same for a given amplitude. 

Connection between Accommodation and Conver- 
gence (Relative Accommodation). — By convergence we 

mean the inward rotation of the eyes which is necessary 
in looking at a near object, in order to obtain single 
vision with both eyes. With each degree of convergence 
of the visual lines a certain effort of accommodation is 
associated. Thus, if the object be situated 2 metres from 
the eye, the visual lines converge to that point, and a certain 
effort of accommodation (0*0 D.) is made. But this connec- 
tion between accommodation and convergence is somewhat 
elastic, for the accommodative effort may be increased or 
decreased, while the object is kept distinctly in view, and 
the same convergence maintained. That it may be increased 
is shown by the experiment of placing a weak concave glass 



0 ^ ^ 




R 







Fig. 37. — Eye accommodated for 0 which 
forms a distinct image on the retina, R. 
Parallel rays now unite in front of the 
retina at a shorter distance, F. 



30 



DISEASES OF THE EYE. 



[chap. II. 



before the eye, when it will be found that the object is still 
distinctly seen ; and if a weak convex glass be then held 
before the eye the object will also be clearly seen, show- 
ing that the accommodative effort may be lessened without 
affecting vision or convergence. This amplitude of accommoda- 
tion for a given point of convergence of the visual lines, found 
by the strongest concave and strongest convex glasses with 
which the object can still be distinctly seen, is called the 
Relative Amplitude of Accommodation. That part of it which 
is already in use, and is represented by the convex lens, is 
termed the negative part; while the positive part is represented 
by the concave lens, and has not been brought into play. For 
sustained accommodation at any distance, it is necessary that 
the positive part of the relative amplitude of accommodation 
be considerable in amount. 

Moreover, the convergence may be altered, while the same 
effort of accommodatjon is maintained, as is shown by the 
experiment of placing a weak prism with its base inwards 
before one eye. In order that the object may then be seen 
singly, it will be necessary for the eye before which the 
prism is placed to rotate somewhat outwards ; and it will be 
found that the individual can do this, while at the same time 
he sees the object with the same distinctness, showing that the 
same effort of accommodation has been maintained, although 
the angle of convergence of the visual axis is less than before. 

Convergence. 

* Range and Amplitude of Convergence.— The near- 
est point for which the eye can converge and still see single is 
the near point of convergence. The far point of convergence 
is the point at which the visual lines meet when the eyes 
are at rest ; as the position of rest is. one of slight divergence, 
this imaginary point usually lies behind the head, and the 
deviation from parallelism to this degree of divergence 
is known as negative convergence. The amplitude of 



chap. II.] OPTICAL STRUCTURE OF THE EYE. 



31 



to bear 



convergence is the sum of the positive and negative 
convergence. The Range of Convergence is the distance 
between the far and near points of convergence. 

The near point of convergence is found by bringing an 
object, snch as a fine line, up to the eyes in the middle line, 
until it begins to be seen doable. The far point of con- 
vergence or rather the negative convergence, can be 
measured by prisms placed base inwards while the patient 
looks at a distant object. In some cases the eyes are 
parallel or slightly convergent when at rest, and then 
convergence is altogether positive. 

The Unit op Convergence. The Metre Angle. 

If the visual line (El, Fig. 38) of an eye (E) bs brought 
on a point (1, Fig. 38) 1 metre distant from 
it in the median line (M 1), the angle of con- 
vergence (E 1 M) which the visual line thus 
makes with the median line is called the Metre 
Angle. It expresses the degree of convergence 
neces-sary for binocular vision at that distance, 
and is employed as the unit for expressing 
other degrees of convergence. If, for example, 
an object be situated i a metre (i, Fig. 38) 
from the eye, the angle of convergence 
( E h M) must be practically twice as large 
as at 1 metre : C. (Convergence) = 2 metre 
angles. If the object be only i of a metre 
distant, 3 metre angles are required : C. = 3 
metre angles. If the object be situated 2 
metres from the eye, the angle of convergence 
will be only one-half as great as at 1 metre, 
and here C. = \ metre angle; while if the 
eye be directed towards a distant object (D) 
there will be no angle of convergence, and if 
the visual lines be divergent the metre angle 
will be negative. 

N'ow the average normal emmetropic eye 
requires for each distance of binocular vision 
as many metre angles of convergence as it 
require* dioptriee of accommodation. For a 

distance of 1 metre an effort of accommodation of 1 dioptre is re 
quired, and also 1 metre angle of convergence; at » metre from 




Fig. 38. 



32 



DISEASES OF THE EYE. 



[chap. II. 



the eye 2 D of accommodation is required and 2 metre angles ; at 
i metre from the eye 3 D of accommodation and 3 metre angles, and 
so on ; while for distant objects neither convergence nor accommodation 
is required. The positive portion of the average normal convergence 
is about 10 metre angles and the negative 1 m.a. 

THE SENSE OF SIGHT. 

The Sense of Sight consists of three Visual Perceptions or 
Sub-Senses — namely, the Light-Sense, the Colour-Sense, and 
the Forin-Sense. 

* The Light-Sense is the power the retina, or the visual 
centre, has of perceiving gradations in the intensity of 
illumination. A convenient clinical method of testing the 
light-sense is the photometer invented by Messrs. Izard 
and Chibret. On looking through this instrument towards 
the sky two equally bright discs are seen. By a simple 
mechanism one of the discs can be made darker. If 
the eye does not perceive the difference in illumination 
between the two discs within 5° its light-sense is abnormal, 
or we may say its L.D. (Light Difference) is too high. Again, 
if one disc be made quite dark, and be then gradually lighted, 
the patient is required to indicate the smallest degree of 
light, or L.M. (Light Minimum), by which he can observe 
the disc issuing from the darkness. This should not be 
more than 1° or 2°. 

Another good method is that of Bjerrum, in which the 
light-sense is tested by grey letters on a white ground, the 
letters being constructed on the same principle as Snellen's 
Test Types. 

A useful and ready clinical method consists in gradually 
diminishing the illumination of the test-types and comparing 
the acuteness of vision of the patient with that of the 
surgeon, provided the latter have a normal light-sense. The 
L.D. is most affected in diseases of the optic nerve, and 
the L.M. in chorioido-retiual affections. 



Crap, ii.] 



THE SBNSE OP SI (HIT. 



* The Colour-Sense is the power the eye has of dis- 
tinguishing light of different wave-lengths. According to 
the Young-Helmholtz theory, the retina possesses three sets 
of colour-perceiving elements, those for Red, Green, and 
Blue or Violet. These are termed primary colours, all other 
colours being compounds of them. 

According to Hering's theory, the colour-sense and the 
light-sense depend upon chemical changes in the retina or in 
the visual substances contained in the retina. He suggests 
the existence of three different visual substances, the white- 
black, the red-green, and the blue-yellow, by the using up 
or Dissimilation, and restoration or Assimilation, of which 
substances the sensations of light and colour are produced. 
In the case of the white-black substance the sensation of 
white, or of light, corresponds to the process of dissimilation ; 
while the sensation of black, or of darkness, corresponds to the 
process of assimilation. For the red-green and blue-yellow 
substances it cannot be said which colour-sensation implies 
assimilation and which dissimilation. The members of the 
black-white pair can mingle with each other and with those 
of the other two pairs; but the respective members of the 
two-colour pairs (being contrast colours), e.g., blue and 
yellow, cannot unite with each other. 

In testing the colour-sense the spectral colours are the 
best for exact experiments, but the difficulty of producing 
them at every moment, and of combining them, renders them 
of little clinical use. 

The clinical method commonly employed for testing the 
colour-sense is that of Professor Holmgren, of Upsala, which 
is based upon the Young-Helmholtz theory. The test- 
objects used are coloured wools, of which a large number of 
skeins of every hue are thrown together. 

Test T. (inde card on inside of end cover) consists in present- 
ing to the individual, in good dill'iised d:iylight, a pule bill pure 
greet, sample, and requiring him to select out of the bundle 

3 



3 I 



DISEASES OF THE EYE. 



[chap. ii. 



of wools of all colours before him all of those samples which 
seem to him to correspond to the test sample. If this be done 
correctly it is unnecessary to proceed further : the individual 
lias normal colour-sense. Amongst the skeins, however, 
there are some which are termed colours of confusion (greys, 
buiis, straw-colour, etc.) ; and if lie select one, or several, 
of these he is colour-blind. . 

If, now, it be desired to ascertain the kind and degree of 
his defect we proceed to Test II. a. A pink (mixture of blue 
and red) skein is given to be matched. If this be correctly 
done, the person is termed incompletely colour-blind ; but if 
blue and violet, or one of them, be selected, he is red-blind 
(sees only the blue in the mixture of blue and red) ; if he 
select green or grey, or one of them, he is green-blind. 

In order to corroborate the investigation Test II. b may be 
employed. A vivid red skein is given. The red-blind chooses, 
besides red, green and brown shades darker than the red ; 
while the green-blind chooses green and brown shades lighter 
than the red. But it is now very generally recognised, that 
red-blindness and green-blindness invariably go together. In 
violet (or blue) blindness purple, red, and orange will be con- 
fused in Test II.95 ; but this is an extremely rare variety of 
colour-blindness. Total colour-blindness will be recognised 
by a confusion of all shades having the same intensity of 
light, and is also rare. It is impossible by this test for any 
colour-blind person to escape detection, except in the case of 
a small central colour scotoma. 

The individual tested should not be allowed to name the 
colours, but merely to match them, as above described. The 
reason for this is twofold. First, because, although the con- 
genitally colour-blind person is usually unaware of his defect, 
yet experience has taught him which of his sensations are 
called blue, red, etc., by other people; and hence he can 
often apply the right names to colours which he really does 
uot see as such, lie is assisted in (his by whatever of colour- 



CHAP. It.] 



THE SENSE OF SIGHT. 



35 



sight is left to him and by the brightness and saturation 
of the different colours, but is liable to frequent mistakes. 
Again, when the colour-blind person does happen to know of 
his defect he is often desirous of concealing it, either because 
he is ashamed of it or from interested motives. 1 

Edridge Green's theory is that light falling upon the retina liberates 
the visual purple from the rods, and a photograph is formed. The 
decomposition of the visual purple by light chemically stimulates the 
ends of the cones, and a visual impulse is set up, which is conveyed 
through the optic nerve fibres to the brain. He assumes that the 
visual impulses caused by the different rays of light differ in char- 
acter, just as the rays of light differ in wave length. Then in the 
impulse itself we have the physiological basis of light, and in the 
quality of the impulse the physiological basis of colour. He also 
;i."umes that the quality of the impulse is perceived by a special per- 
ceptive centre within the power of perceiving differences possessed 
by that centre or portions of that centre. 

Edridge Green divides the colour-blind into two distinct classes, 
independent of each other, but which may be associated. The first 
class includes those who are not able to see certain rays of the spectrum ; 
their spectrum is shortened at one or both ends. If an individual have 
shortening of the red end of the spectrum, he will not be able to see 
a red light at a distance, though he might be able to pick out all 
the green wools in Holmgren's Test I. A man of this kind, when shown 
the red light of Edridge Green's Lantern Test, declares that there is 
no light visible, thus at once demonstrating his incapacity. The second 
class of the colour-blind make mistakes, not because they cannot 
perceive a certain colon r, but because they are not able to recognise 
tbo difference between the colours, which is evident to normal-sighted 
persons. Normal-sighted persons see six definite colours (points of 
difference) in the spectrum. The second class of the colour-blind 
see five, four, three, two, or one colour, according to the degree of 
the defect ; and they confuse the colours of the normal-sighted, which 
are included in one of their own. If the normal-sighted be designated 
hexachromic, those who see five colours may be called pentachromie ; 
those who see four, tetrachromio ; those who see three, trichromic ; 
those who see two, dichromic ; and the totally colour-blind, mono- 
chromic. 

Edridge Green uses two tests— a Classification Test and a Lantern 



1 More detailed information and Holmgren's test will lie found in 
Appendix I. 



DISEASES OF THE EYE. 



[chap. ii. 



Test. Tbu Classification Test consists of a number of coloured wools, 
silks, cards, and glasses, with four test-colours — orange, violet, blue- 
green, and red. The examinee is asked to name the test-colours, and 
then to pick out from the pile all of similar colour. The Lantern Test 
consists of a lantern and coloured glasses, which can be shown alone, 
or combined or modified by neutral glasses. The examinee is asked 
to name the colour of the light shown. Edridge Green is of opinion 
that the use of colour names is absolutely necessary, or normal-sighted 
persons will be rejected, through paying attention to shade rather than 
to colour. It does not matter what name is applied to a colour ; but 
ground for rejection is afforded when the examinee calls two of the 
main colours of the normal-sighted, as, for instance, red and green, 
by the same name. 

A certain proportion of people (3*5 per cent, of men and 
less than 1 per cent, of women) are congenitally colour-blind 
in greater or less degree, without any diminution in the 
other visual functions. 

Acquired colour-blindness is found in toxic amblyopia, in 
atrophy of the optic nerve, and under some other conditions. 

The Form-Sense (Acuteness of Vision) is the faculty 
the eye possesses of perceiving the shape or form of objects, 
and in clinical ophthalmology the testing of this function 
is an important and ever-recurring duty. 

In order that an individual may have good use of his 
eyes it is necessary, not only that the optic nerve, retina, 
chorioid, and refracting media be healthy, but also that the 
refraction and accommodation be normal. When applied to 
by a patient on account of imperfect sight it is our first 
duty, as a rule, to ascertain accurately the condition of 
refraction and accommodation of his eyes. Should these be 
abnoi'mal, and it be found that by aid of the correcting 
glasses perfect vision is obtained, it may in general be con- 
cluded that the eye is organically sound, and that the 
patient's complaints are due to the defect in accommodation 
or refraction. If the glasses do not restore perfect vision, we 
must then, by the ophthalmoscope and other methods, decide 
the nature of the defect. 



CHAP. II.] 



THE SE.YSE OF SIGHT 



37 



By Acuteness of Vision (V.) is meant the power which an 
eve, or rather its macula hitea, has of distinguishing form, 
any anomaly of its refraction, if such exist, having heen first 
corrected, i.e., while the patient wears the correcting glasses. 

Xow, in order to measure the acuteness of vision we must 
have a normal standard for comparison — i.e., we must find 
what is the size of the smallest retinal image whose form 
can be distinguished. We cannot, of course, measure this 
image on the retina directly ; but, as its size is proportional 
to the visual angle — the angle which the object subtends 
at the eye — it is sufficient to determine the smallest visual 









- 1. ' 


(_ ..4. -rr 








1 

A 





Fig. 39. 



angle under which the form of an object can be distin- 
guished. It has been found, experimentally, that the 
average size of this angle is 5' (Fig. 39). 

In order practically to ascertain the degree of acuteness of 
vision, we place our patient with his back to the light, while 
facing him at a distance of 6 metres, and in good light, fire 
placed Snellen's Test-Types for distance. These types are so 
designed that, at the distance at which they should be seen, 
they each subtend an angle of 5' at the eye. The largest 
type should be seen at 60 metres (Fig. 39) by the normal eye, 
and the types range from this down to a size visible not farther 
off than fj metres. If V = Acuteness of Vision, d = the dis- 
tance from the eye to be tested to the test-types, and D = the 
distance at which the type should be distinguishable, then 
V = For example : if d = 6 metres (a distance which 



38 



DISEASES OF THE EYE. 



[CHAP. II. 



most rooms can command), and if the eye see type D = (i, 
then V = £ = 1, or normal V.; but if at 6 metres the 
eye see only D = 60, which should be seen at 60 metres, 
then V = in short V = 6 divided by the number of the 
type read. 

A series of types resembling the letter E, in various 
positions, is also used for testing illiterates. The types of 
Jaeger for near vision are sometimes used for testing the 
acuteness of V. 

Should the patient's sight be so bad that he is unable to 
read any of the letters, it may be tested by finding at what 
distance he can count the surgeon's fingers ; and if he cannot 
even do that, then his power of perception of light (his 
P.L.) should be tested. This is done by means of a lamp 
in a dark room, the eye being alternately covered and 
uncovered, and the patient being required to say when it 
is " light " and when " dark." If the flame be gradually 
lowered the smallest degree of illumination perceptible will 
be ascertained. 

The eyes must be examined separately, that one not under 
examination being excluded from vision by being shaded with 
the patient's own hand or other suitable screen ; but it must 
not be at all pressed on, as any pressure would dim its vision 
when its turn for examination may come. 

With the advance of age the acuteness of vision undergoes 
a slight but steady reduction, owirig to certain senile changes 
in the eye. 

THE FIELD OF VISION. 

By the Field of Vision (F.V.) is meant flic space within 
which, when one eye is closed, objects can be seen by its 
fellow, the gaze of the latter being fixed the while on some 
one object or point. Thus if, standing on a hill, we fix the 
gaze of one eye on some object on the plain below, the field 



CHAP. II.] 



THE FIELD OF VISION. 



39 



of vision includes not only that object, but many others also 
for miles around it. 

The fixation object is seeu by central or direct vision, its 
imnge being formed on the macula lutea; the other objects 
in the field of vision correspond with as many different points 
in the more peripheral parts of the retina, and are seen by 
eccentric, or indirect, vision. Eccentric vision is of great 
importance for the guiding of ourselves and avoiding obstacles 
in our way. Its use may be realised by the experiment of 
looking through a long small-bore cylinder {e.g., a roll of 
music) with one eye, thus cutting off its eccentric field, while 
the other eye is closed. 

The Dimensions of the Field of Vision may be measured 

for clinical purposes by means of an instrument called the 
perimeter. This is a semicircular metal band, which revolves 
upon its middle point, being in this way capable of describing 
a hemisphere in space. The arc is divided into degrees marked 
on it. from 0 placed at its middle point, to 90° at either 
extremity. At the centre of the hemisphere is situated the eye 
under examination, while the fixation point is placed exactly 
opposite, in the centre of the semicircle, at 0°. A small bit 
of white paper 5 mm. square, the test object, is slowly moved 
along the inner surface of the arc from the periphery to- 
wards the centre, until it comes into view, and this point is 
observed in various meridians. The horizontal, vertical, and 
two intermedial e meridians, at the least, should be examined 
by placing the arc of the perimeter in the corresponding 
planes. 

The boundary of the Held may be noted on a diagram or 
chart ( Fig. 40), which represents the projection of a sphere 
on a plane surface. The radii represent different meridians, 
which may be determined by a dial with pointer on the back 
of the perimeter, while the concentric circles correspond with 
the degrees marked on the arc. A pencil mark is placed on 
the chart at the spot corresponding to tha^t on the perimeter 



40 



DISEASES OF THE EYE. 



[OHAP. II 



at which the test object comes into view, and when the 
different meridians have been examined these marks are 
united by a continuous line, which then represents the outer 
boundary of the F.V. 

The normal F.V. is not circular, but extends outwards 





160"^ I i-f^y fi o 

160 



FIG. 40.— Chart of F.V. of Right Eye. j 

about 95°, upwards about 53°, inwards about 47', and down- 
wards about 65°, as represented by the strong curve in Fig. 40. 
The limitation upwards and inwards is partly due to the pro- 
jection of the supra-orbital margin and the bridge of the nose, 
but also to the fact that the outer and lower parts of the 
retina are less practised in seeing than arc the upper and 
inner parts, and their functions consequently less developed. 



CHAP. 1 1 .] 



THE FIELD OF VISION. 



1 1 



The acuteness of vision diminishes progressively towards the 
periphery of the field, two points of a certain size close 
together beiDg distinguishable from each other only a short 
distance from the fixation point, while the farther towards 
the periphery the larger must be the test objects. 

Fig. 41 serves to illustrate the projection of the field of 
vision on the semicircle of the perimeter to its extreme 
temporal (95 r ) and its extreme nasal (47°) boundaries, as well 





Fio. 41. 

as the portion of the retina (a to b) \ which corresponds to 
this extent of field ; and it shows that the sensitive portion 
of the retina, or rather perhaps the portion of the retina 
which is most used, extends farther forward on the nasal 
than on the temporal side. The diagram also explains the 
remarkable fact that the field extends in the temporal 
direction more than 90°. 

It must be remembered, too, that the fields of vision overlap, 
(Fig. 42^ as the two visual axes meet at the fixation point. 



42 



JUS EASES OF THE EYE 



[CHAP. II. 



The Blind Spot of Mariotte is a small blind island or scotoma 
in the F.V., situated about 15° to the outer side of the point of 
fixation and just below the horizontal meridian. It is shown 
as a white spot in Fig. 43. It is due to the optic papilla 
(optic disc), for at that place the outer layers of the retina 
are wanting, and hence it possesses no power of perception. 
There are also, occasionally, minute blind spots in the field, 



50 




70° 



Fig. -12. — Binocular Field of Vision. The white area is comyRon to 
both eyes, P. being the fixation point. The shaded portion on the 
right belongs to the right eye alone, while that on the left belongs 
to the left eye alone. 

due to large retinal vessels, which interfere with the format ion 
of the image upon tl e layer of rods and cones. 

The field of vision may also be tested by means of a 
blackboard ; although peripheral contractions cannot be 
discovered in this way, it is very useful for detecting 
central defects (see Toxic Amblyopia). 

The presence of a gross alteration in the field may be 
roughly ascertained if the observer face the patient, who 
has his back to the light, and use his own hand as a test 
object. The eye of the observer which is opposite the 
patient's eye serves as a control, as its field can be tested 
at the same time as that of the patient's eye, 



chap, ii.] THE FIELD OF VISION. 43 



Pathological Defects in the Field of Vision.— 

These may consist in Contractions or in Insular Defects. 
Contraction of the field takes place either concentrically, that 
is to say to an equal extent all around the periphery, or 
irregularly, for instance on the nasal or temporal sides alone. 




Fig. 43 (Landolf).— Chart of F.V. of Left Eye. 

Occasionally sector-like defects occur. Loss of one half 
the field is known as Hemianopsia. A defective island in the 
field of vision is called a Scotoma and it may be central— 
that is, involving the fixation point— eccentric, or peripheral. 
A defect in the field is Positive if it be visible to the patient 
; ,s a dark area, Negative if it be invisible. If the blindness 



1 1 



DISEASES OF THE EYE. 



[chap. II. 



be complete, the defect is said to be Absolute; but if tbe 
acuteuess of vision be merely diminished, it is said to be 
Relative. A relative defect may exist for colours only. 
In all eyes tbe blind spot is a negative and absolute scotoma 
in tbe field of vision. 

The Perception of Colours in the Periphery of the Field can 
be examined with the perimeter, by means of bits of coloured 
paper 5 mm. square. It has been in this way ascertained 
that the boundaries of the power of eccentric perception 
tor the different colours do not seem to correspond with 
the boundary for white light, nor do the boundaries of the 
different colours seem to coincide. Examining from the 
periphery towards the centre by ordinary daylight, blue 
is the colour which can be distinguished as such most 
eccentrically, its field extending nearly as far as the general 
F.V. ; then come yellow, orange, red, and, with the most 
limited field, green. Blue, red, and green being the most 
important, their fields are noted in Fig. 43. Although the 
respective colours are distinguishable within the limits in- 
dicated, they are by no means so brilliant in hue as when 
seen by direct vision. It has, however, been demonstrated 
that every colour is recognisable up to the outer limit of the 
F.V., if the coloured object be of sufficient surface and be 
sufficiently illuminated ; so that there is, in fact, no absolute 
colour-blindness in the peripheral parts of the retina, but 
merely a diminished sensitiveness to coloured light. 

The Perception of Form in the Periplwry of the Field is 
very defective, and its examination is not of much practical 
importance ; but this portion of the field is very sensitive to 
the movement of objects. 



CHAPTER III. 



ABNORMAL REFRACTION AND 
ACCOMMODATION. 

Ametropia. — It has been explained (p. 24) that, in 
Emmetropia or Normal Refraction, the retina is at the 
principal focus of the dioptric system. When the retina 
does not coincide with the principal focus, parallel rays no 
longer meet on it, if the accommodation be at rest ; this 
condition is called Ametropia (a, priv. ; fxerpov, standard ; 

or an error of refraction. There are three varieties 
of Ametropia. 1. Myopia (p,vebv, to close ; co^r), or Short-sight ; 
in which the principal focus lies in front of the retina. 
2. Hypermetropia (virep, over ; /xerpov, standard ; in 
which the principal focus lies behind the retina. 3. Astig- 
matism (a, priv. > CTTuy/xa, a point), in which the refraction 
of the eye in its different meridians is different. 

Myopia, or Short-Sight. 
Definition and Optical Causes of Myopia— Myopia is 

an error of refraction in which the retina lies behind the 
principal focus of the dioptric system, and in which therefore 
parallel rays of light (a b, Fig. 44) are brought to a focus, 
not on the retina, but in front of it (at/), and form on it 
circles of diffusion (c d). 

Compared with emmetropia, therefore, the refraction of 
the myopic eye is increased. This may be due to shortening 
of the focal length by an absolute increase in (lie refraotive 



46 



DISEASES OF THE EYE. 



[chap. ill. 



power of the eye, brought about by increase of the curvature 
of the cornea, as in conical cornea, or of the crystalline lens, 
as in spasm of accommodation (Curvature M.), or by altera- 
tion in the refractive index of the crystalline lens (Index M.), 





3 


i 






- 1 





Fm. 44. 

as in some cases of commencing cataract, but in these the 
myopia is only of secondary importance. 

The most common cause of myopia is an elongation of the 
antero-posterior axis of the eyeball (Axial M.), and in this 
case the increase of the refraction is therefore only relative. 

Far Point (Punctum Remotum, R), of the Myopic 

Eye. — The myopic eye cannot see distant objects (at six 





/ . 




















\ 



Fig. 45. — Far point of a myopic eye. 



metres or more) distinctly, because of the circles of diflusion 
(c d, Fig. 44), but if the object be brought closer, its conjugate 
focu's (§16, Chap. 1.) will lie further back than/, Fig. 44, and 
when the object readies a certain point nearer to the eye. say 1!. 



CHAP. III.] 



MYOPIA. 



17 



Fig. 45, its conjugate focus will meet the retina (at c) and it 
will be distinctly seen. This point — which is the furthest point 
of distinct vision — is the Far Point or Punctuni Remotuin 
(R.). The myopic eye is therefore adapted for seeing near 
objects. Conversely rays emerging from c will unite at 
R, which is the conjugate focus of the retina. It will be 
observed that, in myopia, R is real and can actually be 
measured, that it lies in front of the eye and is a positive 
quantity. As the position of R in front of the eye deter- 
mines the nature of the error of refraction, so the degree of 
error depends on the distance of R from the eye ; the longer 
the eyeball the closer is R, and the greater is the error of 
refraction. In other words the error of refraction (?•) is 

the inverse of the distance of the Far Point (R), ?" = p, and 



conversely of course R = -. These are general equations 

for all errors of refraction. 

Optical Correction Of Myopia. — The optical correction 





a * 

*. - — 


- 




L 

L 





Fio. 40.— Correction of myopia. 



of an error of refraction is accomplished by placing a lens 
in front of the eye which renders it emmetropic, or enables 
it to briny parallel rays (a, b, Fig. 46) to a focus on the 
retina, without any effort of accommodation, and thus 
tenders the vision of distant objects distinct. Since rays 
diverging from the punctual remotum (R, Kg. 46) are 



-is 



DISEASES OE THE EYE. 



[chap. hi. 



brought to a focus ou the retina in the myopic eye, the 
correcting lens, L, must evidently give to parallel rays such a 
degree of divergence before they pass into the eye, as though 
they came from this punctum remotum. This lens must 
therefore be a concave or diverging lens, and its principal 
focus must be at E, ; that is to say, the focal length of the 
lens must be equal to the distance of the far point from 
the eye, in this case 14 cm. The focus of the glass and the 
punctum remotum of the eye are then identical ; and there- 
fore, parallel rays, after passing through the glass, will have 
a divergence, as though they came from the punctum re- 
motum, and will form an exact image of the distant object 
on the retina. It is evident that the glass will also make 
the rays emerging from the eye parallel. The numher of 




Fig. 47.— Effect of the position of the lens in the correction of 

myopia. 



the glass, in this case, -7 D (= W), will indicate the degree 
of the myopia— i.e., by how many dioptres the refracting 
power of the eye is in excess of that of an emmetropic eye. 
The longer the eye-ball the shorter is the distance of the far 
point from it; and therefore the shorter must be the focal 
length of the correcting lens, and the higher must be its 
number. The degree of myopia, therefore increases with 
the elongation of the eye-ball. 

In the explanation of the correction of myopia given 
above, it is assumed that the correcting glass is in contact 



chap, in.] MYOPIA. 



with the cornea. In practice, however, the glass is placed a 
short distance in front of the cornea, and consequently, must be 
stronger than the theoretical correction. For example : if 
the punctum remotum (Fig. 47) be situated at 20 cm. from 
the eye, then the number of the correcting lens in contact 
with the eye, and the real measure of the myopia, will be 
— 5 D, because the focal distance of this lens is 20 cm. 
Q£p = 5). But if, in the above case, the distance from cornea 
to glass be 2 cm., the required lens in practice will be — 5 - 5 
D = 5-5). Evidently, the further the lens is from the 

eye the stronger it must be ; and it is therefore advisable that 
correcting lenses should be worn at the same distance from 
the eye as are the trial lenses when used to measure the degree 
of ametropia. In the example just given the difference 
between the theoretical and practical amount of myopia is 
very slight, but it becomes greater the higher the myopia. 
In a theoretical M. of 20 D, the lens required at 2 cm. would 
be - 33 D. 

Diagnosis and Determination of the Degree of 

Myopia. — The degree, or amount, of myopia, may be 
determined either objectively by the ophthalmoscope, or 
subjectively by means of the trial-lenses and test-types. 

Si ijjective Method. — Examining each eye separately, we 
find the correcting glass by placing our patient as directed in 
the section on Acuteness of Vision (p. 27). Having first 
tested V. without a glass, a weak concave trial-glass is then 
placed before the eye under examination, and higher numbers 
are gradually proceeded to, until that glass is reached which 
gives the eye the best distinguishing power for the types. 
In order to save time, the distance of the far point can be 
found approximately with small print, and the degree of M 
deduced. A lens a little lower than this may be taken to 
commence with. We often find that there are several glasses, 
with each of which the patient can sec equally well. The 
weakest of these i* the measwre of his myopia. When a higher 

4 




fio 



glass than this is used the patient may still see well, but he 
does so only by an effort of accommodation (i.e., the crystalline 
lens has to be made more convex, in order to compensate for 
the excessive concavity of the glass placed in front of the eye), 
and the glass employed represents then, not merely the myopia 
present, but also this accommodative effort. It is a serious 
mistake to prescribe too strong concave glasses for a myopic 
individual, as will be seen further on. 

The Ophthalmoscopic Methods will be explained in detail 
in chapter iv., and merely require to be mentioned here. 

Direct method at a distance. — The retinal vessels are visible 
and appear to move in the opposite direction to the motion 
of the observer's head. 

Indirect method. — The optic disc appears to increase in size 
when the object lens is drawn away from the patient's eye. 

Direct method. — The fundus and vessels are indistinct, 
and the lowest concave glass which makes them distinct is 
the measure of the myopia. 

llotinoscopy. — With a plane mirror the shadow moves 
against the direction in which the mirror is rotated, provided 
the observer is further from the patient's eye than the far 
point of the latter. 

The Amplitude of Accommodation in Myopia. — The myopic eye has an 
excess (if refractive power (r) as compared with the emmetropic eye : 
therefore, in calculating its amplitude of accommodation, this excess 
must be subtracted from the positive refractive power (/>), which would 
be required to adapt the emmetropic eye to the same pimctum proxi- 
mum ; or, in other words, the myopic eye has need of less accommoda- 
tive power than the emmetropic eye, because, even al rest, it is adapted 
for a distance (R., its puuetum remotum) for which the emmetropic 
eye has to accommodate; hence in myopia 

a =p — r. 

For example: a myope of 4 D who can accommodate up to 11 cm. 
(p = = ! ' L 1 ) uas an amplitude of accommodation of ii — 4 = 5 D. 

Range of Accommodation in Myopia. — In myopia both K. and I'., ami 
therefore the range of accommodation, are broughl closer to the eye. 
The range is also shortened as can he seen from Fig. 18, which shows the 
range of Ac. with an amplitude of 8 D, in Em., and in M. and H. of 3 D 



CHAP. III.] 



MIOPIA. 



51 



respectively. In this case R, is known, from the refraction (R =- 

= a = 33 cm.) ; it remains therefore only to determine P. We saw 
above that in M. a = p — ?•, therefore p = a + r — 8 + 3 = 11 D, and 



P. = - =-i> T = 9 cm. 



rU=0 



8D 




[{-33 cm 



Si 



3D 



9 cm. 



^ 09 



8*3 =11 D 



R=-33 cm 



20 cm 



51) 



p.=a-r 
8-3- 



5D 



Fl(J. 4*. — I!ange of accommodation in emmetropia (E.), in myopia 
(M.)i and hypermetropia (H) of 3 D. each, the amplitude of accom- 
modation in all cases being 8 D. 

The Angle y in Myopia. — In myopia, owing to the length of the eye- 
ball, the cornea is cut closer to its centre by the visual line (M. V., 
Kg. 49) than in emmetropia ; or, by displacement of the macular region 




I'kj. 49. — Angle y in emmetropia (Em.) myopia (M.), and 
hypermetropia (II.). 

the visual line and the optic axis (A O) may coincide ; or, the cornea may 
Wen \x: out. to the outside of its centre by the visual line. In any of 
these cases, but especially in the latter, the effect will be that of an 
apparent convergent strabismus. 



52 



DISEASES OF THE EYE. 



[chap. Ill 



Etiology. — -Myopia is rarely congenital. Infants arc 
hypermetropic, but as they grow the eye tends to be- 
come less hypermetropic, emmetropic, or in some cases 
myopic. Myopia is almost wholly a result of civilisa- 
tion, and its development and progressive increase is due 
to the use of the eyes for near work, such as reading, 
sewing, drawing, etc., which causes elongation of the 
antero-posterior axis of the eye. It is more common in 
cities than in the country, and occurs especially in the 
higher schools, among professional classes, and those oc- 
cupied with fine work. Opinions are divided as to the way 
in which close work causes myopia. Some look upon the 
effort of accommodation as the cause, while others attribute 
it to the pressure exercised on the eyeball by the recti 
or oblique muscles during convergence. Heredity also 
plays a certain part which, however, is not quite clear ; 
but, it would seem that some anatomical or constitutional 
predisposition must be transmitted to the offspring. Finally, 
the higher degrees of myopia are very constantly compli- 
cated with disease of the posterior pole of the eye (called 
by some posterior sclero-chorioiditis, and regarded by them 
as an inflammatory condition), and how far this disease is 
either the consequence or the cause of the elongation of 
the globe has yet to be decided. 

It should also be stated that anything which encourages 
approximation of objects to the eye such as defective print, 
bad light, or indistinctness of vision, e.g., astigmatism, and 
nebulse of the cornea, may act as indirect causes. The 
development of myopia, may also be assisted by anything 
which tends to produce congestion of the head and eyes, 
such as stooping over books, as a result, for instance, of 
badly constructed school desks. In rare instances, myopia 
lias been observed to develop or increase considerably after 
a severe illness. That it is not always due to close work, 
is shown by the facts thai high degrees of myopia are very 



CHAP. HI.] 



.)/ yon a. 



53 



occasionally met with in young children before they have 
begun to use their eyes much for near objects ; and that 
the worst cases may sometimes be met with in agricultural 
labourers, who have done little or no close work. 

Myopia, as a rule, tirst shows itself from the eighth to 
the fifteenth year, and is apt to increase, especially during 
the early years of puberty. After this the majority of cases 
remain stationary, but others continue to increase during the 
whole lifetime, either periodically or regularly, and may 
reach 30 D or more. 

Simple, or Non-Progressive Myopia. — In this variety 

the M ceases to increase when the body has reached its full 
development, and does not, as a rule, go beyond three or 
four dioptres. The eye is perfectly sound and presents 
no disease of the fundus, except occasionally a slight 
crescent at the outer side of the optic disc (see below). 
This form of myopia is sometimes regarded as a harmless 
adaptation of the eye to the requirement of civilisation, and 
as being different in its etiology from the progressive form 
which is a true disease. Unfortunately it is not possible to 
distinguish with certainty one form from the other in the 
earliest stage. But if a patient of sixteen years of age or 
more, have a low degree of M., say only of 2 D or 3 D, and 
especially if there be no crescent, one may be fairly confident 
that the M. will become stationary when the patient is fully 
grown. 

>/)'iHmodic Myoj)ia — that is to say, M. due to spasm of 
accommodation — is a condition which is not uncommon, and 
one which is frequently seen, during the transition of 
EL or Em. into M. The M. disappears under atropine, 
only to return when the use of the latter is discontinued. 

Symptoms of Myopia. — The symptoms of M., apart 
from the complications which occur in the high degrees, 
and which will be dealt with later on, are dependent on 
the optical error of the eye, and are very few. Distant 



54 DISEASES OF THE EYE. [chap. ill. 



vision is impaired according to the degree of M. present, 
but many short-sighted people half close their eyes in order 
to diminish the size of the diffusion circles on the retina, 
aud they are thus enabled to see a little better. It is this 
habit which has given rise to the term myopia (p. 45). The 
smallest print can be distinguished with great facility, at or 
within the near point ; and as the retinal images are larger 
than in emmetropia and consequently require less illumina- 
tion for their perception, short-sighted persons are much given 
to reading in bad light. If the patient reads at his far point 
no accommodation is necessary, and for a nearer point the 
accommodation being less than in emmetropia, one of the 
stimuli to convergence is deficient, and in some cases this 
leads to latent, or even to absolute divergence (see Insufficiency 
of Convergence (chap, xviii.). 

The particles which normally float in the vitreous humour 
are rendered more noticeable by the larger shadows which 
they cast on the retina ; and this is one of the reasons why 
myopic people are so frequently troubled by black spots 
(muscaj volitantes) before their eyes. That short sight 
improves with age, or is the strongest kind of eye, is a 
fallacy which owes its origin to the absence or delayed 
onset of presbyopia in myopic people ; and also to the fact 
that, in low degrees of myopia, the vision may improve a 
little at a distance owing to the small size of the pupils 
in old people, or to the slight diminution in the refractive 
power of the lens which occurs at about sixty years of age 
(cf. Presbyopia). 

Progressive Myopia frequently becomes complicated 

with Organic Disease, and to the more serious cases the 
term Pernicious Myopia may be applied. The following 
are the forms of organic disease met with : — 

1. Posterior Staphyloma, or Myopic Crescent. — This condition 
is recognised by the ophthalmoscope as a more or less ex- 
tensive white crescent at the outer circle of the optic papilla. 



CHAT. 111.] 



MYOPfA. 



55 



Fig. 50 explains the manner in which it arises. The 
bulging of the eyeball, at X , takes place at the posterior 
pole, in the direction of the axis A X. The chorioid c 
becomes drawn towards the temporal side, and the optic 
nerve appears to be displaced in the opposite direction. 
The chorioid is, consequently, drawn over the edge of the 
scleral opening at the nasal side at n, while it becomes 
detached and drawn away from it at the outer side at t, 
the portion of sclerotic thus exposed appearing as a white 







r 


c) 


A 




Fig. 50.— 


Explains 



formation of my- 
opic crescent. 




L.IV. 

Fig. 51. — Small 
myopic crescent. 
M. = 4D. 



L.IV. 

Fig. 52. — Large pos- 
terior staphyloma sur- 
rounding optic disc. 
M. = 0D. 



crescent at the temporal edge of the disc (Fig. 51). As the 
bulging increases, with increase of the myopia, it extends to 
the nasal side of the nerve as well, the chorioid also becoming 
atrophied ; and the posterior staphyloma is then seen with the 
ophthalmoscope completely surrounding the disc, but always 
larger at the temporal side. The stretching of the retina 
may, in extreme cases, derange its functions and increase the 
size of the blind spot. The disc itself appears oval, owing to 
the oblique position, which the nerve head acquires (Fig. 52). 



56 



DISEASES OF THE EYE. 



[OHAP. HI. 



The size of the staphyloma generally corresponds with the 
degree of M. although exceptions to this occur. Every 
case in which a small crescent is present is not to be regarded 
as serious; for much here depends on the age of the patient 
and the degree of the myopia. The younger the patient 
and the higher the myopia, the more serious is the outlook. 

2. Chorioidal Degeneration in the Neighbourhood of the Macula 
Lutea. — This should always be carefully looked for, as the region 
of the yellow spot is very liable to disease in the worst cases 
of progressive myopia. The disease seems to begin in the 
chorioid, giving the appearance of small cracks or fissures, 
which, at a later period, develop into a patch of chorioidal 
atrophy. The retina at the yellow spot becomes gradually 
disorganised, and very serious disturbance of vision, asso- 
ciated in the early stages with metamorphopsia, is the 
result, the patient being disabled from reading, although, 
as the periphery of the fundus is usually sound, he can 
find his way about freely. Treatment can do little here. 
Abstention from use for near work, and the wearing of 
dark glasses are to be recommended. 

3. Chorioidal Exudation in the Neighbourhood of the Macula 
Lutea. — A small grey spot of exudation may appear in the 
chorioid at this place, accompanied by loss of sight for read- 
ing. These cases are often amenable to active mercurial 
treatment, when sight may be restored. Should the case 
be neglected or run a bad course, vision will be permanently 
damaged from secondary chorioidal degeneration. 

4. The Black ,Spot in Myopia. — This disease also attacks 
the chorioid in the region of the yellow spot, and causes 
a loss of central vision, as in the two previous forms of 
disease. The appearance shown by the ophthalmoscope is 
that of a black spot, usually quite circular and with a 
denned margin. In the early stages its size is much smaller 
than that of the papilla, but later it often attains a dimen- 
sion of two papilla diameters, or more. The spot is rarely 



CHAP. III.] 



.1/ YUPIA. 



57 



of an equal intensity of blackness all over, but towards its 
centre a faint reddish hue often shines through in places. 
At a later stage the black spot becomes surrounded by a 
narrow whitish border, while towards its centre it becomes 
less black, and finally greyish or even white, its margin 
remaining black. Although small haemorrhages, which often 
occur in the neighbourhood of the black spot, gave rise to 
the opinion that the black spot itself was the result of 
haemorrhage, yet this seems not to be so, as the investiga- 
tions of E. Lehmus have shown. The disease consists in 
a proliferation of the pigment epithelium, combined with a 
gelatinous exudation, which in the case examined had at- 
tained a thickness, at the centre of the black spot, of two- 
thirds that of the chorioid. The chorioid was but very slightly 
altered, and the glass membrane was quite normal. At the 
margin of the proliferating region the pigment epithelium 
was found to be paler or even quite free of pigment. The 
black spot very gradually, in the course of years, attains 
its ultimate dimension, and then very slowly retrogresses, 
until finally its place is taken by a greyish or bluish-white 
scar. Treatment is of no avail, and central vision does not 
become restored. 

5. General Clwrioidal Atrophy. — In advanced cases of per- 
nicious myopia, large patches of chorioidal atrophy, other 
than the crescent, are often present, chiefly in the region 
of the posterior pole, but often also towards the periphery 
of the fundus. The vitreous humour in these cases is more 
fluid than normal, and usually contains many opacities. 
Treatment by means of sub-con junctival saline injections is 
occasionally of use in clearing up the vitreous humour, and 
thus effects some improvement of vision. The eyes should 
not be used for near work, and dark glasses should be worn. 

Haemorrhage in the Retina at the Yellow Spot may occur, 
and when the haemorrhage becomes absorbed the macula lutea 
may not recover its function, owing to the delicate retinal 



58 



DISEASES OF TEE EYE. 



[chap. III. 



tissue having been seriously damaged. Yet we often meet 
with cases of this kind which do regain their former vision. 
Kest of the eyes and da rk glasses should be prescribed. 

7. Detachment of the Retina. — This is a frequent, and most 
serious complication of progressive myopia, and sometimes 
leads to secondary cataract and even to shrinking of the eye- 
ball (Phthisis Bulbi). It will be considered in the chapter 
on Diseases of the Retina. 

In high degrees of M. the eyes are unduly prominent, and 
the sclerotic appears flatter at the sides ; the pupils are 
usually large and the anterior chamber deep, owing to the 
slight development of the ciliary muscle in consequence of 
the non-use of accommodation. 

Functional Anomalies attending Progressive 
Myopia. — 

(a) Insufficiency of Convergence is almost always asso- 
ciated with progressive myopia, and is the result of two 
causes, namely the diminished impulse to convergence pro- 
duced by the absence of accommodation, and the mechanical 
ditheulty introduced by the elongation of the ejes. The 
in.su tliciency of convergence may be only latent, or it may 
lead passively to absolute divergent strabismus (see chap, 
xviii.). 

(Ji) Cramp of Accommodation is often present and causes 
an apparent increase in the Myopia (see p. 53). 

The Management of Myopia.— In view of the tendency 

to increase, to . which, especially during adolescence, nearly 
every case of short-sight is liable, and of the fact that in 
a given case we cannot tell to what extent this increase 
may go, and, finally, as the high degrees almost invariably 
lead to disease of the eye, the management of myopia, 
including the prescribing of glasses for it, is one of the 
most important matters with which we have to deal. 

The Prescribing of Glasses in Myopia. — It is not necessary 
to prescribe glasses for very slight degrees of myopia (up to 



CHAP. III.] 



MYOPIA. 



59 



TO D or 1'5 D); yet, should the patient desire to wear correct- 
ing glasses for distant objects, there can be no objection to it. 
But for cases of myopia of 2*0 D or more, unless presbyopia 
be also present, it becomes very desirable to prescribe glasses 
which fully correct the myopia, to be worn constantly- — i.e., 
for both distant and near objects ; and, should the myopia 
increase, to accordingly increase from time to time the 
strength of the glasses. 

This has not always been the teaching on this point, and 
even yet many ophthalmologists do not prescribe fully 
correcting glasses for their myopic patients, especially for 
near work. It has been held, that any effort of accommoda- 
tion, which might be caused by fully correcting concave 
glasses, would promote the tendency to increase of the 
short-sight, and to chorioidal disease. In short, it was 
regarded as important to save the myopic eye every effort of 
accommodation in so far as possible. The usual practice was to 
order a glass from 0 - 5 D, to 2 D less than the full correction 
for distant vision ; while, for near work, either no glasses were 
allowed, if the myopia was of low degree, or, if of medium or 
high degree, a separate pair of spectacles, of such strength 
as would merely enable the patient to read ordinary print 
at about 30 cm. from his eyes, was given. It was also 
the practice to restrict the use of the myopic eye for 
near work to a limited number of hours daily, with intervals 
of rest, or even to interdict all near work absolutely for a 
period of months at a time. The main object of the reading- 
glass was — the patient being enabled thereby to hold near 
objects farther from his eye — to diminish the angle of 
convergence of the optic axes, and thus to reduce the pressure 
of the orbital muscles on the eyeball during convergence, a 
pressure which it is considered promotes the elongation of 
the globe. 

We now know, on the one hand, that the action of the 
muscle of accommodation does not produce a pull on the 



60 



[chap. hi. 



chorioid farther back than the equator of the eyeball, while 
it is at the posterior pole that the diseased processes in 
myopia commence. Nor does the ciliary muscle by raising 
the tension of the eye, nor in any other way, cause an 
elongation of the eyeball. Hence, there is no reason to 
spare the healthy myopic eye any ordinary effort of accom- 
modation. Indeed, it is reasonable to think that if normal 
efforts be required of the ciliary muscle, its more healthy 
tone will improve the general healthy nutrition of the uveal 
tract, and consequently will tend rather to avert morbid 
changes in it. 

On the other hand, the diminution of the angle of con- 
vergence at near work is a truly important matter, for the 
reason above stated; but it is more effectually provided for 
by full than by partial correction. 

Practical experience is here even more valuable than 
theory, and it shows that in a large majority of those 
patients whose short-sight has been fully corrected in youth, 
and who have worn their spectacles constantly for a number 
of years, the myopia in many instances has not increased at 
all, while in a large proportion the increase will have been 
moderate, and in but a small proportion marked pernicious 
progress will be noted. In short, the tendency to increase of 
the myopia, and to organic disease, is less than in those 
myopes who have either worn no glasses, or only partially 
correcting glasses. 

Well-fitting, properly centred spectacles are much to be 
preferred to folders, which are difficult to keep correctly 
centred before the eyes. Any astigmatism present should 
always be corrected. Patients whose eyes are healthy, and 
who wear constant full correction, may be permitted, and 
even encouraged, to use their eyes freely for near work, 
always keeping the work as far from the eyes as possible, 
to diminish the angle of convergence. With this latter 
object in view, too, well printed books, ample light, and 



CHAP. III.] 



MYOPIA. 



61 



suitable reading- and writing-desks should be provided in 
all educational establishments, and for home studies. 

But in prescribing the full correction for constant wear 
to young short-sighted persons, we meet with some difficulties. 
The first of these is due to the range of accommodation, 
which is imperfect in the myopic eye, and consequently the 
patients may complain of painful accommodative sensations 
when first using their fully correcting lenses for near work, 
and sometimes they decline to persist in the attempt. These 
complaints are more likely to be made by patients of about 
twenty years of age or more, whose habit of use of their 
eyes (relative amplitude of accommodation, and degree of 
convergence) has become more or less confirmed, and in whom 
the power of accommodation has naturally diminished to an 
appreciable degree, rather than by persons of from twelve to 
seventeen years of age. Patients should be encouraged, in 
spite of discomfort, to continue for some time longer to 
read, etc., with the full correction, when, very often, the 
relative amplitude of accommodation will gradually improve, 
and the discomfort will cease. Or, a lower number than the 
full correction may be ordered, and the strength gradually 
increased, until, in the course of some weeks or longer, the 
full correction can be worn for near work with ease. 

Operative Cure of Myopia. — This consists in diminishing the refrac- 
tion of the eye by the removal of the crystalline lens. Some surgeons 
simply extract the clear lens, while the majority now, including the 
anthors, perform discission, followed, in a few days, by the evacuation 
of the swollen and catnractous lens, and in some cases by a subsequent 
capsnlotomy. A larger number of operations than this is apt to be in- 
jnrious ; moreover, the swollen lens should be removed before the tension 
of the eye becomes increased. For both of these reasons, therefore, 
simple discission without extraction is inferior to the other method. 
There are grounds for suspecting that, in these highly myopic 
fives, the tendency to retinal detachment is increased by the operation, 
althongh this has not been shown by statistics. 

The ojierative cure of myopia is not to he recommended except for 
cases of 120 I) and more; nor should it be performed where there is 
rach serious disease of the fundus or vitreous humour as would render 



62 



[CHAP. III. 



any improved use of the eye on conclusion of the treatment unlikely. 
Active chorioidal disease is regarded as a contra-indication, but small 
retinal haemorrhages, even if they be near the macula lutea, need not 
be so regarded. The best time of life for the cure is in childhood or in 
early youth, but it can be successfully undertaken at a much later 
period. In the myopic eye the nucleus of the lens undergoes sclerosis 
to a less extent than in hypermetropia or in emrnetropia. and hence in 
it discission is less apt to be followed by high tension or other complica- 
tion, even when performed in middle age. 

The advantages gained by the patients from the operative cure of 
their myopia are very great. Not merely do they become sometimes 
emmetropic, but the. acnteness of vision is usually increased in a 
remarkable degree, being occasionally even double or treble that 
which previously existed with the correcting glasses. This improve- 
ment is chiefly due to the increased size of the retinal images. The 
reduction in the refraction is much greater in these cases, than after 
removal of the lens for cataract in an emmetropic eye. In the latter 
case a convex lens of 10 D is required to correct the eye for distance, 
whereas a myope of 20 D most commonly requires no correction for 
distance after the removal of his lens. The explanation of this is simple. 
When the lens is removed, the only refracting surface is tben the 
cornea, the focal length of which is approximately 31 mm.; a myopic 
eye therefore which is 31 mm. long would, when deprived of its lens, 
bring parallel rays to a focus on the retina and would require no 
correction Tor distance. Since the average focal length of the 
emmetropic eye is 24 mm. this myopic eye would be 31 — 24 = 7 mm. 
longer. Now it can be easily shown that, in the complete eye con- 
taining the lens, every millimetre of increase in length corresponds to 
an increase of 3 D of refraction, consequently in this case before 
operation, when the lens was present, the refraction would have been 
increased by 3 x 7 = 21 L), a result which agrees in most cases with 
practice. 

In the absence of the lens an increase of 1 mm. in length only 
augments the refraction by about 1-5 D, that is to say, only half 
the amount which the same increase of length produces in the complete 
eye. A simple rule therefore for finding approximately what the 
refraction will be, after removal of the lens, in a given case of myopia, 
is to take half the number of dioptres of the myopia and subtract ii 
from 10, if the result be positive a plus lens will be required after 
operation, and if negative a concave lens. For example, a myope of 10 D 
will require a + 5 D Tor correction after operation, 10 — V = ">, and 
a myope of 30 D will remain with 5 1) of myopia, 10 — n 3 ° = — 6. Tn 
practice cases sometimes occur which do nol agree with theory, and 
for this there are reasons which cannoi be fully entered into here, bni 
amongsl them is the difficulty of an exacl estimation of the refraction 



CHAP. III.] 



HYPERMETROPIA. 



63 



in high M. and the possibility of the M. being, not merely axial, but 
also caused by shortening of the focal length of the dioptric 
system. 

The mere possibility that detachment of the retina may be caused, or 
hastened, by the operation is a sufficient reason for limiting the 
operation to one eye. It is wiser not to operate on the second eye, 
even though a successful result may have been obtained in the first, 
and though the patient, as often happens, may desire it. The eye 
which has been operated upon, will serve for distant vision and its 
fellow for near work, and thus, where the eye after operation becomes 
emmetropic, the patient is rendered independent of glasses. It has 
not been proved that removal of the lens arrests the progress of 
myopia 

Hypermetropia. 
Definition, and Optical Causes.— In Hypermetropia the 

retina lies in front of the principal focus of the dioptric 
system, and therefore parallel rays of light (a, b, Fig. 53), 
falling into the hypermetropic eye (E), do not meet on the 
retina, but converge towards a point (c) situated behind it. 




Via 53. 



As compared with emmetropia the refraction of a hyper- 
metropic eye is diminished. It may be caused by displacement 
of the retina forwards, from shortening of the eyeball (Axial 
H.), or by elongation of the focal length of the dioptric 
system through flattening of the cornea (Curvature IT.), 
or absence of the lens. 
Far Point (R.) of the Hypermetropic Eye.— Since 

parallel rays do not unite on the retina, but produce (here a 
circle of diffusion (ft,e, Fig. 53), the hypermetropic eye cannot 



64 



DISEASES OF THE EYE. 



[chap. hi. 



see distant objects distinctly, and if an object be brought closer, 
its focus will lie still further behind the retina (§17, chap. i.). 
There is therefore no position between infinity and the cornea, 
from which rays of light would unite on the retina of the 
hypermetropic eye ; in other words, there is no real far point. 
What kind of rays then will come to a focus on the retina 
of a hypermetropic eye 1 The answer will be found by 
considering the course of the rays emerging from the eye. 
Since the refraction is deficient or, what is the same thing, 
since the retina lies in front of the principal focus F. Fig. 
54, (see §18, chap, i.) rays coming from any point (c), 




Kiu. 54. 



will not even be rendered parallel, but will pass out as 
divergent rays (/', </), and they can therefore never meet to 
form a real conjugate focus, or far point. But they will 
diverge as if they came from a point E, situated behind the 
eye, which point is the virtual conjugate focus of the point c 
on the retina. It is the virtual far point. It is situated 
behind the eye, is negative, and cannot be measured directly 
as in myopia. Conversely, if the rays f,g, enter the eye with 
a convergence towards R, they will unite on the retina. 
The hypermetropic eye therefore is only adapted, when at 
rest, for convergent rays. The shorter the eyeball, the 
further the retina is from F, and the greater the divergence 
of the emerging rays, and consequently the shorter will be 
the distance of the far point, and the higher the error of 



CHAP. HI. J 



HYl'KllMWmOPIA. 



retraction. In hypermetropia, as in myopia, r — p-, bnt here 

B is negative, and therefore r, the error of refraction, is also 
a negative quantity. 

Optical Correction of Hypermetropia. — In order to 

correct hypermetropia — that is, to render the eye emme- 
tropic, so that parallel rays may be brought to a focus on 
the retina (c, Fig. 55) — a lens must be placed in front 
of the eye, which will give to the parallel rays (a, b) 




Fig. 55. — Correction of hypermetropia. R = far point, r = error of 

refraction. 



before they enter it a convergence towards its far point, 
R. This lens must therefore be a converging or + lens, 
and its focal length must be equal to the distance of R 
from the eye (in this case 25 cm.). The negative error, or 
deficiency in the refraction, is corrected by a + lens (L), 
which increases the refraction, and thereby shortens the 
focal length of the eye so as to bring the focus on to the 
retina. The shorter the antero-posterior axis of the eyeball, 
the closer is R (see p. 64), and the shorter therefore must 
he the focal length of the correcting lens. That is to say, 
the correcting lens must be stronger, and the hypermetropia 
Consequently greater, when the eye is shorter. 

It is evident that the further the lens (L) is from the 

5 



66 



DISEASES OF THE EYE. 



[chap. hi. 



cornea the greater is its distance from It, and therefore the 
weaker the lens which is required. This is the reverse of 
what takes place in myopia (p. 48). 

Hypermetropia can also be corrected by an effort of 
accommodation, in which the increased convexity of the crys- 
talline lens within the eye takes the place of the correcting 
glass. In the case represented by Fig. 55, an accommodation 
equivalent to 4 D would be required. 

Determination of the Degree of H. Subjective Method 

BY tkial-lenses and test-types. — Since accommodation tends 
to correct hypermetropia, care must be taken in drawing 
conclusions from this method of examination. If the acute- 
ness of vision be improved by a convex lens, H. is present, 
but it may be found that, with a lens of some dioptres less, 
the eye will see equally well ; this means that an effort of 
accommodation supplements the weaker lens placed before 
the eye. As higher lenses are proceeded to, the effort of 
accommodation is relaxed, until, finally, the strongest lens 
with which vision is still at its best is reached, when, it may 
for the present be assumed, no further effort of accommoda- 
tion is made, and this lens then represents the whole error 
of refraction. 

In low degrees of hypermetropia, accommodation fre- 
quently corrects the whole of the H. When such an eye 
is found to have full vision without a glass, a beginner may 
fall into the error of regarding it as emmetropic ; but if 
he will take the precaution of placing a low convex lens in 
front of it, and then finds that the acuteness of vision 
remains as good as without the glass (because the effort of 
accommodation is now relaxed), he will avoid this mistake, 
unless there should be tonic cramp of accommodation, which 
might partially, or even completely, mask (he hypermetropia. 

If a glass a single number higher than the exact measure 
of the defect bo placed before the eye, vision again becomes 
indistinct, because the rays are then brought to a focus in 



CHAP. III.] 



HYPERMETR OPIA. 



67 



front of the retina, and a circle of diffusion is formed on the 
latter. The eye, in fact, is put by such a glass in a condition 
of myopia. Therefore the strongest convex glass with vjhich a 
hypermetropic eye can see distant objects {the test-types) most dis- 
tinctly is the glass which corrects its hypermetro]ria, and is the 
measure of the latter. Very commonly it is only the manifest 
h vpermetropia (vide infra) which is ascertained by this method, 
unless the accommodation has been previously paralysed by 
atropine. 

Ophthalmoscopic, or Objective tests. Direct Method at a 
Distance. — The retinal vessels are visible, and appear to move 
in the same direction as the motion of the observer's head. 

Indirect Method. — The optic disc appears to diminish in 
size as the lens is withdrawn from the patient's eye. 

Direct Method. — The strongest convex glass with which 
the fundus and vessels can be seen distinctly is the measure 
of the H. 

Retinoscopy. — With a plane mirror the shadow moves in 
the same direction as that in which the mirror is rotated, 
that is to say, with the mirror. 

Amplitude of Accommodation in Hyperinetropia. — When at rest, the 
refraction of the hypermetropic eye is deficient, consequently r must be 
negative ( — r), and the amplitude of accommodation must include the 
correction required to adapt the eye to infinity ; therefore the formula 
for the amplitude of accommodation (p. 27) becomes 
a — p — ( — r) =2> + r. 

For example : if the punctum proximum of a hypermetropic eye of 
5 D be at 30 cm., what is the amplitude of accommodation ? 5 D 
(=r) is necessary in order to make the eye emmetropic, and to 
accommodate the emmetropic eye to 30 cm. 3*25 D (J^p. == 3*25) is 
required. Hence a = 3 25 + 5 = 8-25 D. 

Eange of Accommodation in H. — In hypormetropia a part of the 
patient's amplitude of accommodation is used to correct the error of 
refraction, the remainder only being available for the purpose of 
adapting the eye for a near point. It follows, therefore, that, with 
the same amplitude of accommodat ion as an emmetrope, the near point 
will be further away from the eye in hyperinetropia. This is shown in 
Ms.'. 1*. which represents the ranges of accommodation in emmetropia 



68 



DISEASES OF THE EYE. 



[chap. III. 



(E.), myopia of 3 D (M.), and hypermetropia of 3 D (FL), the amplitude 
being 8 D. 

The Angle y in Hypermetropia — In hypermetropia, as in emmetropia, 
the cornea is cut to the inside of its axis by the visual line; but in 
hypermetropia the angle which the visual line forms with the optic 
axis is greater, owing to the shortness of the eyeball, the effect of 
which is to increase the angular distance between the macula lutea 
and the optic axis (OA, Fig. 49). Consequently, in extreme cases, 
when the two visual lines of a hypermetropic individual are directed to 
an object, the axes of the corneas may seem to diverge, and thus the 
appearance of a divergent strabismus will be given (see apparent 
strabismus, chap, xviii.). 

Varieties of H. in Relation to Accommodation.— 

Hypermetropes endeavour to correct as much of the error 
of refraction as possible by accommodating, and the ciliary 
muscle is thus kept persistently contracted. 

This spasm is not, or may be only partially, relaxed when 
the correcting convex glass is held before the eye, and con- 
sequently the whole or part of the hypermetropia may be 
masked by the cramp. That part of the hypermetropia 
which is thus masked is called latent (HI.), while the part 
which is revealed by the convex glass with which the 
test-types are read is called manifest (Hm.). The entire 
hypermetropia is made up of the latent and manifest IT. 
(H. = Hm. -f HI.). 

If the Hm. cannot be corrected by accommodation it is 
called absolute H., if it can be so corrected it is known 
as facultative. For example, a patient without glasses has 
V = 3^, and with 4- 1-5D, V = |; with 2-5 D also, V = 
but when accommodation is paralysed the H. is found to bo 
4 D. In this case the total H. is 4 D, the Hm. is 2-5 D, of 
which 1-5 D is absolute and ID facultative, while there is 
1-5 D latent H. The relation between the Hm. and H. 
varies with the age and general health of the individual. 

When the spasm persists so that the accommodation cannot 
be relaxed, the vision is then made worse, even by a weak 
convex glass, thus simulating emmetropia. In this case we 



CHAP. HI.] 



11 YPEiniF/rnopiA. 



69 



say that the whole hypermetropia is latent. Or, in extreme 
cases of accommodative spasm, parallel rays may be united 
in trout of the retina, and the eye made apparently myopic, 
distant vision being capable of improvement by concave 
glasses (see p. 53). Some of these patients cannot maintain 
a sustained view of an object at any distance without 
suffering pain in and about the eyes. Examination with 
the ophthalmoscope, or paralysis of accommodation with 
atropine, will enable the surgeon to avoid mistakes. 

In order to relieve this cramp, or to ascertain the real 
state of the refraction, especially in children, atropine must 
be freely instilled ; and it will often be necessary to keep 
the accommodation paralysed for some days, and to com- 
mence the use of the correcting spectacles before the effect 
of the atropine begins to wear off*. In this way a recurrence 
of the spasm may be often prevented. 

As life advances, and the power of accommodation 
diminishes, the manifest part of the hypermetropia increases, 
while the latent part decreases, until finally Hm. = H. 

Etiology. — Typical hypermetropia is practically always 
axial, i.e., due to a short eyeball. Children are hyperme- 
tropic at birth, but with the growth of the body the eye 
develops and becomes less hypermetropic, or emmetropic, or 
even myopic. So that the hypermetropic eye may be 
regarded as an undeveloped organ, and indeed the highest 
degrees of H. are met with in very small (microphthalmic) 
eyes, which are often the subjects of congenital malforma- 
tions. The eyes of animals and of uncivilised nations are 
also hypermetropic. When the period of growth ceases, 
any H. which may then exist remains stationary. There 
U never any progress, as in myopia ; and very high degrees 
arc rarely seen, even 12 D being unusual. Hypermetropic 
eyes are moreover healthy, and free from the complications 
which follow mechanically from the change in shape of the 
myopic eye. 



7(1 



DISEASES OF THE EYE. [CHAP. III. 



Symptoms of H. — These depend chiefly on the relation 
of the H. to the amplitude of accommodation, and will be 
understood from what has been already stated. Both distant 
and near vision may be perfect, or near vision alone may 
be defective, or both may be imperfect. In high degrees 
of H. patients sometimes hold the book close to the eyes 
in order to obtain larger retinal images, but they cannot 
read the smallest type with the ea|se and fluency of the 
myope. Slight redness and veiling of the edges of the optic 
disc with tortuosity of the retinal vessels is sometimes seen. 
Other consequences are accommodative asthenopia, and 
convergent strabismus. Hypermetropic eyes show increased 
curvature of the sclerotic at the outer side, when the eye 
is rotated inwards, the pupils are smaller than in Em., and 
the anterior chamber shallow. 

Accommodative Asthenopia (a, priv. ; a-divo*, 

strength; a>yj/), — This is the name given to the group of 
symptoms which occur when the patient is unable to 
sustain the accommodative effort required for near vision. 
A hypermetrope, having used up part of his accommoda- 
tion for distance, has for near objects actually less at his 
disposition than an emmetrope. Hence, hypermetropic 
people often complain of inability to sustain accommodative 
efforts for near objects for any length of time. After 
reading, sewing, etc., for a short time, sensations of pressure 
in the eyes, and of weight above and around them come 
on, and the words or stitches become indistinct, and cannot 
be distinguished, and the efforts to see are attended with 
frowning and even with facial contortions. The work must 
then be interrupted, and after a few minutes' rest it can be 
resumed, but must soon again be given up. After a 
Sunday's rest the patient is often able to get on better 
than on the previous Saturday. These symptoms depend 
simply upon inability of the ciliary muscle to answer to the 
excessive demands made upon it. 



Ill AT. III.] 



ASTIGMATISM. 



71 



Accommodative asthenopia often appears suddenly during 
or after illness, the explanation being that, although hyper- 
metropia had always existed, yet in health the ciliary muscle 
was equal to the great efforts required of it, but in sickness 
it shared the debility of the system in general. 

Internal, or Convergent Concomitant Strabismus. 

— This condition has a certain relation to hyperrnetropia. 
It will be treated of in the chapter on the Motions of the 
Eyeballs and their Derangements (chap. xvii.). 

The Prescribing- of Spectacles in Hyperrnetropia. — 

If a person be found to be hypermetropic, but his acuteness 
of vision without glasses be good, or as good as he desires, 
and he complain of no asthenopic symptoms, glasses need 
not, indeed should not, be prescribed for him. No disease in 
his eye will result from his going without glasses. 

If the patient complain of imperfect distant vision due to 
hyperrnetropia, then those lenses which correct the Hm. may 
be prescribed for distant vision, to be worn either constantly 
or occasionally, as he may desire. Such a patient is almost 
certain to complain also of accommodative asthenopia ; while 
many patients will be met with who complain of the latter, 
yet express themselves as perfectly satisfied with their distant 
vision. For relief of the asthenopia it is usually enough 
to prescribe spectacles for near work which will correct the 
Hm., along with 1 D or 2 D of the HI., if the latter exist. 

If there be excessive cramp of accommodation, glasses to 
correct the whole hyperrnetropia should be worn while the 
eye is under atropine ; and afterwards as much of the HI. as 
possible, along with the Hm., should be corrected by glasses 
to be worn constantly. 

Astigmatism. 

In this form of ametropia the refracting surfaces are 
not spherical, and consequently, rays of light from a luminous 
point are not brought to one focus. The defect usually 



72 



DISEASES OF THE EYE. 



[CHAP. J 1 I . 



lies iu the cornea, and the astigmatism may be regular or 
irregular. 

In Regular Astigmatism the directions of the greatest and 
least curvatures of the cornea are always at right angles to 
each other, and usually fall precisely in the vertical and hori- 
zontal meridians, the meridian of greatest curvature being 
most frequently the vertical. The surface of the cornea then 
resembles the back of the bowl of a spoon, which is more 
convex from side to side than from heel to point. Astigma- 
tism is said to be " with the rule " when the meridian of 
greatest curvature is vertical, and, " against the rule," 
when this meridian is horizontal. Hence a pencil of rays 




Fig. 56. 



passing into the eye, instead of meeting at a common focus, 
is irregularly refracted, those rays passing through the vertical 
meridian of the cornea being brought to a focus much earlier 
than those which fall through its horizontal meridian ; and 
therefore at the focus of the former the latter rays form 
a horizontal streak of light. The interval between the foci 
of the two principal meridians is called the Focal Interval, 
and is a measure of the astigmatism. 

Fig. 56 shows the different forms which the image of a 
point assumes after the passage of the rays through an 
astigmatic surface. 

At A neither vertical (v v) nor horizontal (A h') rays have 
yet been united at their foci, but the vertical rays are the 
nearest to their focus ; and therefore here the appearance 
of the image on an intercepting screen, is an oval with its 
long axis horizontal, as shown by the dotted line. At B 



CHAP. lit.] 



ASTIGMATISM. 



73 



bhe vertical rays have met at their focus, but the horizontal 
rays not as yet at theirs, the effect being a horizontal 
straight line. At 0 the vertical rays are diverging again 
From their focus, and the horizontal rays have not come 
to theirs. At D the same conditions exist, only a little 
farther on, where one set of rays is diverging, the other 
still converging, but each at the same angle ; hence the 
figure is a circle. At F the horizontal rays have met, 
and the result is a vertical straight line. At G both 
sets of rays are divergent, and the figure is an oval with 
the long axis perpendicular. 

There are various kinds of regular astigmatism, according 
to the position of the two principal foci with reference to the 
retina, as follows : — 

1. Compound Hypermetropic 
Astigmatism. — Both foci behind 
the retina, that of the hori- 
zontal rays (H, Fig. 57) farther 
back than that (V) of the vertical 
rays. Hypermetropia in both 
meridians, but greater in the 
horizontal. 

2. Simple Hypermetropic Astig- 
matism.— Thefocusof the vertical 
rays (V, Fig. 58) on the retina 
(emmetropia in that meridian) ; 
that (H) of the horizontal rays 
behind the retina (hypermetropia 
in that meridian). 

o. Mixed Astigmatism. — The 
horizontal focus (H, Fig. 59) 
behind the retina (hypermetropia 
in that meridian), and the ver- 
tical focus (V) in front of the 
retina (myopia in that meridian). 




Fig. 57. 




Fig. 58. 




71 



DISEASES OF THE EYE. 



[chap, in, 




Fig. 60. 




Fig. 61. 



4. Simple Myopic Astigmatism. 
— The horizontal focus (IT, 
Fig. 60) on the retina (eniuie- 
tropia in that meridian), the 
vertical focus (V) in front of the 
retina (myopia). 

5. Compound Myopic Astig- 
matism. — Both foci in front of 
the retina, but the vertical focus 
further forward (V, Fig. 61). 

Symptoms of Astigmatism. 

— -We may conclude that an in- 
dividual is astigmatic if he see 
horizontal (or vertical) lines, 
such as the horizontal portions of Roman capital letters, 
or the horizontal lines in music, or the horizontal rays in 
Snellen's Sunrise figure (see end of this book) distinctly, 
while the vertical (or horizontal) lines seem indistinct. 
We have such a complaint, for example, when the retina 
is situated at the focus of the parallel rays passing through 
the vertical meridian of the cornea. 

Suppose an eye to be emmetropic in the vertical meridian, 
and ametropic in the horizontal meridian : we must first 
consider how a point will be seen by such an eye. The rays 
of light emitted from the point and passing through the 
horizontal meridian will not be brought to a focus on the 
retina, but will produce a blurring of the retinal image 
of the point at each side ; while the vertical rays will unite 
on the retina, and consequently the point will appear distinctly 
defined above and below. 

A line may be regarded as a number of points, and in 
order to understand how lines will be seen by an as- 
tigmatic eye, such as the above, it is only necessary to 
arrange a number of points blurred at the sides in 
vertical and horizontal lines — as at a and b in Fig. 62. 



CHAP. III.] 



ASTIGMATISM. 



75 



It is evident at once from mere inspection that the hori- 
zontal line will appear distinct, because the rays which diverge 
from each point of the latter in a vertical plane — i.e., at 
right angles to the direction of the 
line — are brought to a focus on the 

retina ; while those rays diverging m ^ y y -y-^ ^ 

in a horizontal plane, although 

not meeting on tbe retina, do not 

render the picture of the line in- y w ( . 9 

distinct, because the diffusion images 

resulting from them exist in the horizontal direction, and 
consequently cover or overlap each other on the line, and 
therefore are not seen and do not confuse the sight. At the 
ends of the line only (b, Fig. 63) do the diffusion images 
cause a fuzziness or make the line seem longer than it 
is. In this case a vertical line (a, Figs. 62 and 63) seems 
indistinct, because, the horizontal meridian being out of 
focus, the diffusion images existing in that direction are 
very apparent, as they are at right 
«e angles to the edge of the line. On the 

other hand, in order to see a vertical 
^^^^■^^^^e 5 stripe accurately, it is necessary only 
that the rays diverging in a horizontal 
plane should have their focus on the 
retina ; and, therefore, if an individual 
can only see vertical lines distinctly at 6 metres we know 
that his eye is emmetropic in the horizontal meridian (and 
probably myopic in the vertical meridian). We do not, 
however, hear this complaint as often as might be expected, 
because simple astigmatism is not so common as one or other 
of the compound forms. 

Astigmatic people do not generally see very distinctly, 
either at long or at short distances. 

Even in hypermetropic astigmatism the book is very 
often brought close to the eyes, in order, by increasing 



76 



DISEASES OF THE EYE. 



[CHAP. III. 



the size of the retinal image, to make up for its indis- 
tinctness. 

Astigmatic individuals frequently sutler much from head- 
ache, due to constant effort to see distinctly, and the correc- 
tion of the astigmatism often cures it. 

It has been stated that epilepsy, if not capable of being 
actually produced by refractive errors, especially by astig- 
matism, in persons with stable brains, may sometimes have 
such errors as its exciting cause, where there is already a 
predisposition to the disease. 

All these signs and symptoms appertain to the rather 
high degrees of astigmatism. Slight degrees may cause no 
annoyance beyond some indistinctness of vision ; and indeed 
slight degrees of hypermetropic astigmatism often pass un- 
noticed until late in life, when the accommodation begins 
to fail. But very low degrees of astigmatism may give 
rise to symptoms in neurotic individuals. Astigmatism, 
contrary to rule, or with the axis obliquely placed are the 
forms most likely to cause annoyance. 

We are often led to suspect and to seek for astigmatism 
when, in examining the refraction with spherical glasses, we 
are able to bring about some improvement of vision, but can- 
not obtain normal V. with any glass, while there is no organic 
disease to account for the defect. Also if, in examining with 
spherical glasses, we hnd V. benefited equally by several 
glasses of considerable difference in power, even perhaps by 
convex as well as by concave glasses. 

The ophthalmoscope affords us an admirable means of 
diagnosing astigmatism, and of determining its amount. J ust 
as the astigmatic eye cannot see horizontal and vertical lines 
equally well at the same moment, so is an observer unable 
to see both the vertical and horizontal vessels in the retina 
of the astigmatic eve simultaneously, but must alter his 
accommodation to be able to see first one set of vessels 
and then the other. 



CHAP. III.] 



ASTIGMA TISM. 



77 



A comparison of the shape of the optic papilla, as seen in 
the upright and in the inverted images, may also give a clue to 
the presence of astigmatism. Inasmuch as the fundus oculi is 
very much magnified in the upright image by the dioptric media 
through which it is seen, and as this enlargement is greater 
in the direction of the meridian of shortest focus (meridian 
of highest refraction), which is most commonly the vertical 
meridian, a circular object, such as the papilla, will seem to be 
of an oval shape with its long axis vertical. But in the in- 
verted image, if the principal focus of the lens be closer to 
the eye than 13 mm. (anterior focus of the eye), the mag- 
nification will be less in the meridian of greatest refraction ; 
and here, consequently, the round optic papilla is seen as an 
oval with its long axis horizontal. If the principal focus of 
the lens be further from the eye than 13 mm., the magnifi- 
cation again becomes greater in the meridian of greatest 
refraction, and the oval again becomes vertical. Sometimes 
tin' papilla is really of an oval shape, and not round, and 
then the diagnosis is readily made by observing that in one 
image it is seen as an oval, while in the other image it is 
circular. Care must be taken in the indirect method not to 
hold the lens obliquely, as this would be sufficient to make 
a circular disc appear oval, the long axis of the oval being 
in the direction of the axis round which the lens is rotated. 

In astigmatic eyes a crescent, similar to that seen in 
myopia, is often present at the margin of the optic disc. 
It lies parallel to the meridian of higher refraction. 

In cases of corneal astigmatism the image of Placido's 
disc, (see chap, vii.), reflected on the cornea, shows ellipses 
instead of circles, the short axes lying in the meridian of 
greatest curvature. 

The Estimation of the Degree of Astigmatism and 

its Correction. — It is evident that to correct astigmatism 
the ordinary spherical lenses would be of little use, for they 
affect the refraction of the light passing through them equally 



78 



DISEASES OF THE EYE. 



[chap. in. 



in every direction. Cylindrical lenses (p. 14) are therefore 
employed, which refract light in one direction only — viz., at 
right angles to their axes. 

Subjective Method. — Although astigmatism is now- 
a-days almost universally estimated hy means of (he 
ophthalmoscope, or by the astigmometer (see p. 81), yet in 
order to give the student a clear idea of the matter in the 
simplest way, a subjective method for its estimation will 
be now described, while its objective estimation by aid of 
the ophthalmoscope (erect image and retinoscopy) will bo 
treated of in the next chapter. 

Simple Astigmatism. — Snellen's Sunrise (vide diagram at 
end of book), or some such diagram, is placed at 6 metres 
from the eye (the other eye being excluded), and the patient 
is asked whether there be any line which he sees much more 
distinctly and blacker than the others, and can trace farther 
towards the central point. If that be so, he must be emme- 
tropic in the meridian at right angles to that line, provided 
his accommodation be at rest, and ametropic in the meridian 
corresponding to that line. 

In case the horizontal line below at each side be the distinct 
one, the eye is emmetropic in the vertical meridian, and pro- 
bably hypermetropic in the hoi'izontal meridian, because the 
latter is generally that of least curvature. Consequently, a 
convex cylindrical lens held with its curvature horizontally 
(axis vertical) before the eye will correct the defect. The 
highest convex cylindrical glass which gives the patient the 
best possible distant vision will be the correcting glass. This 
would be a case of Simple Hypermetropic Astigmatism 
(As. H.). If the lens required be + 2 D Cyl., it would be 
As. H. 2D; and in prescribing for the optician we should 
write " + 2 D Cyl. Ax. Vert." 

If the central vertical line be the distinct one, then em- 
metropia exists in the horizont a l meridian, and probably there- 
fore myopia in the vertical meridian; and a concave cylindrical 



CHAP. III.] 



ASTIGMATISM. 



79 



lens held before the eye with its curvature vertical (axis hori- 
zontal) will correct the defect. The lowest concave cylindrical 
lens which gives the patient the best possible distant vision 
will be the correcting lens. This would be a case of Simple 
Myopic Astigmatism (As. M.). If the lens be — 2-5 Cyl., it 
would be As. M. 2-5 D ; and for the optician we should 
write « — 2-5 D Cyl. Ax. Horiz." 

The reader should now make a few experiments for 
himself with cylindrical lenses, by means of which he can 
produce artificial astigmatism in his own eye. Let him place 
Snellen's Sunrise figure opposite his eye at a distance of 
about 4 to 6 metres. If he now hold a + TO Cyl. before 
his eye, with its axis horizontal, it gives a myopia of l'O D 
to the vertical meridian of the eye, while the horizontal 
meridian remains emmetropic ; and consequently, he will 
see the central vertical line of the diagram distinctly, while 
the horizontal lines will be indistinct. By placing a — TO Cyl. 
with its axis horizontal before the eye, in addition to 
the -f- TO Cyl., the artificial astigmatism produced by the 
latter is corrected, and the whole diagram becomes distinct. 
Every other kind and degree of astigmatism can be similarly 
represented by lenses and similarly corrected. 

* Compound Astigmatism. — If no line be very distinctly 
seen, then the examination may be commenced with Snellen's 
Distance Test-Types, and the patient tested in the ordinary 
way with spherical lenses until one be found which gives the 
best distant vision. This is placed in a spectacle-frame before 
the eye, and the meridians of greatest H.-4 d 
and least curvature of the cornea are 

ascertained, as explained already. If 

the spherical lens be + 4 D, and with 
it the horizontal lines in the Sunrise 
Diagram be the most distinct, then the vertical meridian is 
Shown to be corrected, and the eye is probably still hyperme- 
tropic in the horizontal meridian, and requires a -f cylindrical 



K. I I> + H. 1 D 



80 



DISEASES OF THE EYE. 



[cuap. in. 



lens with its axis vertical, in addition to the spherical lens, 
to correct the entire defect. Suppose this cylindrical lens be 
found to be -f- 1 D. Cyl., then the H. in the horizontal meridian 
will be shown to be 5 D, and the astigmatism to be 1 D. 

This will be noted as : "H.4D + As. H. 1 D Horiz," ; 
or, ns for the optician, " + 4 D Sph. Q + ID Cyl. Ax. Vert." 1 
This is Compound Hypermetropic Astigmatism. 

In an analogous way the examination is made for 
Compound Myopic Astigmatism, in which every meridian 
is myopic, but the vertical more so than the others. 

* Mixed Astigmatism. — Lastly, cases are met with in which 
both concave and convex spherical lenses produce a certain 
amount of impi'ovement, but neither give full vision. Placing, 
then, one or other before the eye in the spectacle-frame, the 
examination is proceeded with by aid of Snellen's Sunrise. 
The lowest concave spherical lens which will bring out one 
horizontal ray distinctly is ascertained. Let this be — 3D; 
there is then myopia of 3 D in the vertical meridian. 
Now, having removed the — lens, the highest convex lens 
which will bring out one vertical line distinctly is ascer- 
tained. Let it be + 5 D ; this indicates hypermetropia of 
that amount in the horizontal meridian. We may correct 
such a case in either of two ways : («) by a Sph. — 3D, 
which will correct the vertical meridian, but will increase the 
M.3D hypermetropia. in the horizontal meridian by 

3 D, making it 8 D, which can then be 

corrected by combining a cylindrical lens 

of + 8 D, axis vertical, with the above 
spherical lens ; (b) by a spherical + 5 D, 
which will correct the horizontal meridian, but will increase 
the myopia in the vertical meridian to 8 D, necessitating the 
combination of a — Cyl. lens of that number with the 
+ 5 D Sph. For reading, writing, etc., an over-correction 



1 The sign 3 indicates "combined with." 



CHAP. III.] 



ASTIGMATISM. 



81 



of the horizontal meridian with + 8 D Cyl., thus rendering 
the eye myopic 3 D in every meridian, and enabling the 
patient to read at, or near, his far point, might be the most 
suitable arrangement. 

As it is necessary, in order to test the degree, etc., of astig- 
matism accurately, that the accommodation be at rest, it is 
desirable, before the examination for any of the hypermetropic 
forms, to instil atropine into the eye. 

* Measurement of the Degree of Astigmatism by the 
A stigmometer. — This is one of the most rapid and satisfac- 
tory methods of determining both the degree of astigmatism, 




Fig. 64. — The Astigmometer. 

and the position of the meridians of greatest and least 
refraction. 

The cornea reflects images of objects in the same manner 
88 a convex mirror, and the smaller the radius of curvature 
the smaller will be the image of any given object. It is 
easy to calculate the radius of curvature of the cornea, if 
the size of the object, its distance from 1 ho cornea, and the 

6 



82 



DISEASES OF THE EYE. 



[chap. III. 



size of the corneal image be known. The only difficulty 
lies in the measurement of this image ; and it has been found 
that the best method of effecting this is to double the image 
by means of prisms, and then to alter the strength of the 
prism until the two images just come into contact. When 
this has taken place, a displacement equal to the size of the 
image has been produced. The amount of displacement, and 
hence the size of the image, can easily be calculated. This is 
the principle of the astigmometer (Fig. 64). 

In order to measure the degree of astigmatism by it, 
we do not require to know the radius of curvature of the 
cornea, but merely to find out the difference in refractive 
power between the meridians of greatest and least curvature, 
and this the instrument enables us to do in a few seconds 
without any calculation. 

It consists (Fig. 64) of a telescope (p) containing a double 
refracting prism between the object glasses, and two reflectors 
or mires (k and I), movable on an arc (m), which is fixed 
to the telescope tube. The latter turns on its own axis, and 
enables the arc to be placed in any meridian, its position 
being indicated on a graduated circle (g). The patient places 
his chin on the rest d. and looks into the tube at/, the eye 



a b J* 

Fig. 65. 

which is not under observation being covered by the disc e. 
The surgeon then looks through the telescope at u, turns the 
arc m into a horizontal position, and observes the corneal 
images of the mires, which he gets into focus. He then 
moves the mires until the central images just conic into 



CHAP. III.] 



ASTIGMATISM. 



83 



contact; the four images will then occupy the relative positions 
shown in Fig. 65. The arc is then rotated into the vertical 
meridian, and if tho curvature of the cornea in this meridian 
be the same as in the horizontal meridian, the central 
images will still appear to be in contact ; but if the radius 
of curvature in the vertical meridian be smaller, the intervals 
a to b and a to b' will diminish, and consequently the central 
images will overlap, as in Fig. 66, each step of a representing 
a difference of 1 Dioptre. So that in this 
case (Fig. 66) there would be an astigmatism 
of 2 D., and the greatest refraction would be 
in the vertical meridian. 

It is generally desirable to begin with the 
arc in the horizontal meridian. If the axes of 
the meridians of greatest and least curvature 
are oblique, then the images will not lie in one line, and 
the arc must be turned until they do so lie. An index which 
moves on the circle g (Fig. 64) gives the position of the 
axes. It will be seen from the above description that the 
astigmometer merely registers the amount of astigmatism, 
but does not enable us to estimate the general refraction 
of the eye. Moreover, it is the corneal astigmatism alone 
which is determined, and it will be found in most cases to 
differ only slightly from the total astigmatism. A useful 
modification in the mires consists in making them of 
complementary colours, for instance, one red and the other 
green, 1 the overlapping portion then appears white and is 
easily seen. Another great advantage which these coloured 
mires possess is the absence of dispersion, due to the use of 
mono chromatic light, which renders the appreciation of the 
">ntact of the images much more delicate. We use the 
latter instrument at the Victoria Hospital, and find that it 
facilitates the observations considerably. 




1 This instrument is made by Pflster and Streit, Berne 



XI 



DISEASES OF THE EYE. 



[chap. hi. 



* Lental Astigmatism. — The astigmatism of the lens when 
at vest is supposed to be about 0-75 D, and contrary to 
the rule, and it tends therefore to correct or diminish 
corneal astigmatism with the rule. This assumption is based 
on the fact, that often, when there is no subjective astig- 
matism, the astigmometer shows a corneal astigmatism 
of 0'75 D with the rule, which the lental astigmatism must 
correct. The theory also accounts for the fact that the 
astigmometer over-estimates the total astigmatism by 0"5 D 
or 0 - 75 D when with the rule, and underestimates it by the 
same amount when against the rule, because in the latter 
instance the lental astigmatism must be added to that of 
the cornea, whereas in the former case, it must be deducted 
from it. This lental astigmatism may be caused by the 
shape of the lens, or by an obliquity in its position. A 
difference between the subjective or total astigmatism, and 
that of the cornea as measured by the astigmometer, 
can also be accounted for by the fact that the visual line 
does not pass through the centre of the pupil, and therefore 
the portion of the cornea measured by the astigmometer is 
not exactly the same as that which produced the retinal 
image. These discrepancies, however, do not detract materially 
from the practical value of the instrument. 

Disturbances of vision due to astigmatism often make their 
appearance for the first time at middle age or even later, 
and are then apt to be mistaken for amblyopia. In such 
cases the cornea has been astigmatic all through life, but the 
defect has been masked by a compensating astigmatism of 
the crystalline lens, produced, it is supposed, by an unequal 
accommodative contraction of the ciliary muscle. When, 
as life advances, the amplitude of accommodation diminishes, 
the power of the ciliary muscle to produce this active com- 
pensatory lental astigmatism also diminishes, and finally 
disappears, and then the corneal astigmatism becomes 
manifest ; or, in astigmatic individuals the astigmatism 



CHAP. III.] 



ASTIGMA TISM. 



85 



may alter in degree at this time of life. Under atropine, too, 
astigmatism may appear, the existence of which was not 
previously known. This is termed active, or dynamic, lental 
astigmatism. 

PrescrijAioii of Cylindrical Lenses. — The position of the axis 
of a cylinder in a prescription is indicated by a line at the 
extremity of which a number indicates in degrees its inclina- 
tion to the vertical or horizontal, as 2 D. Cyl. ax. /' M °. Since 
the axis of cylindrical lenses must occupy a definite and 
unalterable position before the eyes, spectacle frames or 
rigid spiral-spring pince-nez should be ordered, and not 
folders. When first worn, cylindrical glasses frequently 
appear to cause distortion in the shape of objects, and un- 
pleasant sensations of giddiness ; these, however, disappear 
with a little perseverance in the use of the glasses. 

Irregular Astigmatism. 

In irregular astigmatism, the refraction of the eye differs 
not only in different meridians of the eye, but even in different 
parts of one and the same meridian. It is frequently due 
to irregularities in the surface of the cornea, the result of 
former ulcers, and also sometimes to irregular refracting 
power in different parts of the crystalline lens. It cannot be 
corrected. Its presence can be detected by a distortion 
and irregular movement of the disc when the lens is moved 
during the indirect method of examining with the ophthal- 
moscope, and also by an irregular shadow in retinoscopy. In 
Home cases, there is a certain amount of regular astigmatism 
combined with it, correction of which may improve the vision. 

* Anisometropia. 1 

By this term is meant a difference in the refraction of 
the two eyes, one being myopic, hypermetropic, or astigmatic, 



1 d, priv. ; taot, like ; nirpov, a measure. 



86 



DISEASES OF THE EYE. 



[chap. III. 



while the other is emmetropic, or ametropic in a way differ- 
ent from its fellow. So long as the difference in refraction 
is but slight (say 1 D or 1-5 D), it is generally possible to 
give the correcting glass to each eye. When the difference 
is considerable it is often impossible to fully correct each 
eye, because, binocular vision having never really existed, 
the patients are unable to tolerate the presence of a clear 
image on each retina. We must then be content with 
correction of the least ametropic eye, or of that one which 
has the best vision ; or, we may partially correct the most 
ametropic, and fully correct the least ametropic eye. Each 
such case must be dealt with as it permits. 



ANOMALIES OF ACCOMMODATION. 

Presbyopia. 

This is a diminution in the amplitude of accommodation, 
which commences at an early age, and is due to natural 
changes taking place slowly in the crystalline lens. It might 
not therefore, strictly speaking, be considered as an anomaly. 
The power of accommodation commences to diminish in early 
childhood, the near point beginning then to recede from 
the eye. The accompanying diagram of Donders (Fig. 67), 
illustrates the decrease from the tenth year of age, 
and indicates the amplitude of accommodation at different 
ages. 

The numbers along the upper horizontal line refer to 
the ages, those along the left-hand perpendicular line to the 
dioptres. The curve r r shows the refraction of the eye when 
in a state of rest. This is unchanged until the fifty-fifth year, 
when it begins to diminish ; the emmetropic eye then becoming 
hypermetropic, the hypermetropic eye more hypermetropic, 
and the myopic eye less myopic. The curve p p shows the 



chap, in.] Ay OM A LIES OF ACCOMMODATION. 



87 



positive retracting power of the eye, corresponding to the 
punctuni proximum, and its gradual diminution as life ad- 
vances, and how at the age of 65 it becomes even less than 
the minimum refraction in former years. The two curves 
meet at the age of 73, and then all power of accommodation 
ceases. The number of dioptres included between the two 
curves on the vertical line corresponding to any given age 



m ff r» !.r .i/> to t<r ,ro .r.r <x> tf.f m flf 8b 




s \_ 1 I I I | | I I 

Fig. 67. 

represent the amplitude of accommodation at that age — e.g., 
at 30 years of age the amplitude is 7 D ; at 50 years it is only 
2*5 D. The amplitude of accommodation is the same at the 
same age in all forms of ametropia, as well as in emmetropia. 

The cause of presbyopia lies chiefly in a progressive change 
in the crystalline lens, which becomes less elastic and more 
homogeneous in its different layers, and refracts light less 
Jtrongly than before. In more advanced life, diminished 



88 



DISEASES UE THE EYE. 



[CHAP. III. 



energy of the ciliary muscle probably becomes a second 
factor in the production of presbyopia. 

The near point gradually recedes from the eye until it 
reaches a distance beyond that at which the person usually 
reads, writes, sews, etc. Employments of this kind then 
become difficult, because the retinal images are too small to 
be clearly discerned, owing to the increased distance at 
which the work must be held from the eye ; and, in order 
to make up for this smallness of the images, the individual 
is often seen to improve their brilliancy by procuring 
stronger light. 

Presbyopia was defined by Donders to be present when 
the near point lies at more than 22 cm. from the eye, 
and we correct it by giving such a convex glass for reading, 
etc., as will bring the near point back to 22 cm. Now in 
order to see at that distance a positive refracting power 
(j>) of (-2°2 0 - = ) 4 - 5 D is necessary, and if the eye have 
not so much positive refraction, a convex glass must be 
given to it of such power as will bring p up to 4-5 D ; 
and this lens is the measure of the presbyopia. At the 
age of 40 {vide Donders' diagram, Fig. 67) the eye possesses 
a positive refraction of just 4'5 D ; and therefore from 
this age presbyopia (irpeafivs, an old man ; w^r) is said to 
commence in emmetropic eyes. The presbyopia, then, is 
equal to the difference between the positive refracting power 
possessed by the eye and 4' 5 D, and the number thus found 
is the correcting glass for the presbyopia. The distance 
of 22 cm. is rather close to the eyes for the comfort of 
most people, and 33 cm. is more commonly taken as the 
reading distance. Presbyopia on the latter assumption is 
postponed for two or three years. 

The glass required in presbyopia must also depend on the 
nature of the patient's work, which, of course, may require 
to be placed at some definite distance. This distance, the 
refraction of the eye, and the amplitude of accommodation 



CHAP. III.] AXO.UA LIES OF ACCOMMODATION. 



89 



(age of the patient), will determine the number of the glass 
which must be prescribed in each case. 

It is important that in prescribing glasses for presbyopia, 
it' there be any hypermetropic astigmatism present, it should 
be corrected by the suitable + cylinder lens added to the 
spherical glasses. It is also important that the glasses 
should be carefully centred for the reading distance — i.e., 
that the visual lines, when they are converged to the 
distance at which the work is held, should pass through 
the optical centres of the glasses. The glasses must there- 
fore be closer together, and also tilted forwards at the top, 
so that they may be at right angles to the visual axes. 
Moreover, if there be any insufficiency of the internal 
recti, it will be for the patient's comfort to decentre the 
lenses slightly inwards. 

The following table indicates the presbyopia of the em- 
metropic eye : — 



Age. 


p. required. 


p. existing. 


Presbyopia. 


40 




4-5 


4-5 


0 


45 


4-5 


3-5 


1-0 


50 


4-5 


2-5 


2-0 


55 


4-& 


1-5 


3-0 


HO 


4-5 


0-5 


4-0 


65 


4-5 


0-25 


4-25 


70 


4-5 


-1-0 


55 


75 


4-5 


-1.75 


6-25 


80 


4-5 


-2-5 


7-0 



It is hardly necessary to point out that presbyopia comes 
on at a much earlier age in hypermetropes than in eininetropes ; 
while in myopes its advent is postponed; or, in the higher 
degrees of myopia, it may not come on at all. The hyper- 
metrope of 3 D would be presbyopic at the age of 27 ; because, 
in order to arrive at the 4-5 D of positive refraction required, 
he must have an amplitude of accommodation of (3 D + 4 5 D) 
7-5 D, and this he has only up to that age (vide Fig. 07). 



DISEASES OF THE EYE. 



[chap. ill. 



The myope of 4 - 5 D can get along until something over 60 
years of age without any glass for reading (vide above table). 
At 65, if he were emmetropic, he would have presbyopia of 
4-25; consequently he will now require a + glass of only 0-25 D. 

Presbyopia must not be mistaken for slight paralysis of 
accommodation. They are distinguished by the fact that in 
the former the amplitude of accommodation corresponds to 
the age of the patient as given in Donders' table, and the 
difficulty of near vision comes on gradually. 

When presbyopia is associated with ametropia, which 
requires correction for distance, bifocal lenses are very 
convenient. A thin, oval or circular, lens representing the 
addition required for near vision is cemented on to the 
lower part of the distance glass, or is inserted between 
the two portions of which this is formed. 

Paralysis of Accommodation (Cycloplegia). 

This may be partial or complete, and one or both eyes may 
be affected. It is usually combined with paralysis of the 
sphincter iridis (mydriasis), and the condition is then called 
ophthalmoplegia interna ; but it is also seen without paralysis 
of the sphincter, and either alone or with paralysis of 
some of the orbital muscles supplied by the third pair, 
which also supplies the ciliary muscle — rarely with paralysis 
of the external rectus. 

The Symptoms are similar to those of presbyopia, but come 
on rather suddenly. They give inconvenience to the patient 
according to the state of his refraction. If he be emme- 
tropic, his distant vision continues good, while his vision 
for near work is much impeded. If he be hypermetropic, 
as he requires his accommodation for distant objects, vision 
for distance is interfered with, and still more so, vision for 
near objects. If he be myopic, vision is less affected than in 
either of the other forms of refraction ; indeed, if he have 



chap, in.] A. YO MA LIES OP ACCOMMODATION. 



91 



more than i D of M, being able to see near objects at bis far 
point, be may sutler little or no inconvenience. 

Micropsia is a common symptom in cases of partial paralysis 
of accommodation, and is due to the fact that, while the 
retinal image is unaltered in size, the great effort of the 
defective accommodation gives the sensation of the object 
being much nearer to the eye than it really is. 

Causes. — Paralysis of accommodation may be caused by 
poisons acting locally (atropine) or through the system 
(ptomaines, nicotine, lead) ; but it is also the result of, or 
is attendant upon, various diseases. It is one of the 
symptoms of paralysis of the third nerve ; it may be due 
to rheumatism or to exposure to cold ; or it may depend 
upon syphilis, syphilitic periostitis at the sphenoidal fissure, 
syphilitic gumma, or syphilitic inflammation of the nerve 
itself. 

Double paralysis of accommodation is often nuclear. 
Paralysis of accommodation and mydriasis are sometimes 
forerunners by many years of serious mental derangement. 

Diphtheria is a frequent cause of paralysis of accommoda- 
tion, usually without, but sometimes with, mydriasis. The 
onset occurs most commonly some weeks after the throat 
affection, which need not have been of a severe character. 
Indeed, the faucial attack may have had no apparent diph- 
theritic character, and may have been so slight as almost to 
have escaped the notice of the patient, although sometimes 
albumen will be found in the urine. The lesion in these 
cases is probably a nuclear one, and the evidence points to 
miliary extravasations of blood in the floor of the fourth 
ventricle ; but some hold that the paralysis is due to a 
poison, that it is a toxic paralysis. 

In influenza paralysis of accommodation is seen, occurring 
sometimes in the acute stage and sometimes during con- 
valescence. One recorded case went on to bulbar paralysis, 
and ended fatally ; but complete recovery is usual. 



92 



DISEASES UF THE EYE. 



[chap. hi. 



Paralysis of accommodation in middle life may be due to 
diabetes, and should raise the suspicion of the presence of 
this disease. It may also occur in diseases of the spinal 
cord, e.y., locomotor ataxy. 

Blows on the eye are apt to cause paralysis of accommoda- 
tion, usually with mydriasis. 

The Treatment depends, of course, upon the cause of the 
paralysis. The instillation of a 1 per cent, solution of sulphate 
of eserine or of muriate of pilocarpine may be employed in 
all cases, and will at least produce temporary improvement of 
sight ; but it can hardly be said to assist in the cure, except 
perhaps in slight diphtherial cases. Iodide of potassium 
and mercury are indicated in syphilitic cases, and iodide of 
potassium and salicylate of sodium in rheumatic cases. The 
prognosis in these cases must be very guarded, as it often 
happens that recovery does not take place. No further 
symptoms may occur, but in some instances it may be 
followed by external ophthalmoplegia. Where cure does not 
result the patient may be enabled to make better use of 
his eye or eyes by means of a convex glass or spectacles ; 
but in this matter each case must be dealt with for itself — 
no general rule can be laid down. 

In diphtherial cases a general tonic treatment, especially 
iron, is indicated ; and here the prognosis is invariably 
favourable. 

Accommodative Asthenopia 

has been already treated of under the head of Hypermetropia 
(p. 70). 

Spasm ok Accommodation. 

Spasm, or cramp, of accommodation in connection with 
hypermetropia and myopia has already been referred to. A 



chap, in.] ANOMALIES OF ACCOMMODATION. 



93 



Few cases of acute spasm of accommodation have been re- 
ported. Occurring in an emmetropic or slightly hypermetropic 
eye, such a spasm produces apparent myopia. In some of 
the cases there was no assignable cause for the spasm, in 
some it was due to overwork, and in one to trauma of 
the cornea. The treatment is a lengthened course of 
atropine locally. 



CHAPTER IV. 



THE OPHTHALMOSCOPE. 

Before proceeding to describe the ophthalmoscope, a brief statement 
of the properties of plane and concave reflecting surfaces (or mirrors) 
will be of use. 

Laws of Reflection. — When a ray of light. O S (Fig. 68), meets a polished 
surface or mirror, M M, at a given point, S, the angle of incidence, i, 
formed with the perpendicular to the surface, 1', is equal to the angle 
of reflection, and the incident and reflected rays O 8, S E, lie with the 
perpendicular in one plane. 




FIG. OS. — Reflection by a plane mirror. 

Images formed by a Plane Mirror.— To an observer placed at E the 
point O would seem to be at T, where the prolongation of 1! S intersects 
the line I 0 perpendicular to the mirror, and 0 M is equal to M I. 
Similarly the image of the point B is found on the perpendicular B E, 
B L) being equal to D B. The image I E therefore, formed by a plane 
mirror, is virtual, erect, and situated behind the mirror at the same 
distance from it as the object () B. 

Images formed by a Concave Mirror. — In Fig. 69, <■ is the centre of 
curvature of the mirror M M. The rays a, b. parallel to the axis 8/, meet 

94 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



95 



the surface of the mirror at M and M' and are reflected to F the 
principal focus. The angle of incidence a M o being equal to the 
angle of reflection F M o, the radius o M being perpendicular to 
the surface of the mirror at M. F lies midway between S and c; that is 
to say, the focal length of a concave mirror is equal to half the radius. 
Rays from a point /, beyond o, are made to converge at /', between 




Fig. 69. — Reflection by a concave mirror. 

F and c, and the further away / is the nearer will /' be to F ; / and /' 
are conjugate foci. The conjugate focus of a point nearer the mirror 
than F would be virtual, because the rays then diverge after reflection. 

In ophthalmoscopic work the source of light is usually further 
away than the centre of curvature of the mirror, and Fig. 70 shows 
how, in this case, a real inverted and diminished image of the light 
is formed. The image of the point 0 is found at I, the point of 




IfJft, 70. — Image formed by a concave mirror when the object is 
beyond the centre of curvature. 

intersection of the ray O I, which passes through the centre of curvature 
C, without deviation, and the ray O N parallel to the axis, which passes 
through the principal focus F, after reflection; the image of the point 
I ; U found in a similar manner. As O I! approaches C, I M also 
Approaches it. and increases in si/.e until at C object and image are 
f| f equal size and coincide. When the object lies between F and the 



96 



DISEASES OF THE EYE. 



[CHAP. IV. 



mirror a virtual, erect, magnified image is seen. A concave mirror 
therefore resembles a convex lens in its action (chap, i., §§22 and 2ii). 

To distinguish a Plane from a Concave Mirror the 

student should stand with his back to the source of light 
and, with the ophthalmoscope held in front of him and a 
little to one side, should throw the light reflected from 
it into his own eye ; he will then see an erect image, if the 
mirror be plane, or an inverted image, if the mirror lie 
concave. A simpler method consists in facing the source 
of light, and throwing the reflected light on a screen, say 
the palm of the hand, and moving the mirror towards or 
away from it ; then, if the mirror be plane, a round image 
with a dark central spot will be formed at all distances ; 
but, if the mirror be concave, at a certain distance an 
inverted image of the source of light will be foi-med. 

Effect of Displacement of the Image with the Rotation of the Mirror 
round an Axis lying in the Plane of the Mirror. — When a plane 
■mirror is rotated, the image of the source of light moves in a direct inn 
opposite to that in which the mirror is rotated. In Fig. 71 when the 
mirror is rotated from M, to M a the image of the light, L, will be found 




Fig. 71.— Motion of the virtual image in rotation of a plane 
mirror. 

on the perpendiculars to the mirror, M, and M s , at 1, and 1... The cones 
of rays emerging from these images, a, a, and !>., h.,, will move with the 
rotation of the mirror as indicated by arrow B, while the images have 
moved in the opposite direction, shown by arrow A. When a concave 
mirror is rotated, the image moves in the same direction as the mirror. 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



!i7 



In Fig. 72 when the mirror is in the position M 1 , the image of L is 
formed at V, on the secondary axis passing through the centre of 
curvature C ; and, on rotating the mirror into the position M 2 , the 




Fig. 72. — Motion of inverted image in rotation of a concave 

mirror. 

corresponding image will be found on the secondary axis L C 2 , say at I 2 , 
the change of position of the image being in the direction of the 
arrow, and with the movement of the mirror. 

The Ophthalmoscope. — Although the dioptric media of 
an eye may be perfectly clear and normal, yet no detail 
of its fundus can be discerned by the unaided eye of an 
observer who looks through the pupil, the latter being for 
him merely a dark opening. The reason of this is, that 
light can only enter the eye through the pupil and the 
refractive media. In albinos the pupil appears red, because 
the absence of the uveal pigment allows the light to pene- 
trate the sclerotic and illumine all the interior of the eye 
in a diffuse manner. To explain : — Suppose the inside of 
a small box {vide Fig. 73) to be blackened, and on its 
floor some printed letters fastened, and a hole cut in 
the lid, which is then replaced — it will be found that, by 
aid of a lighted candle and with a little experimentation, 
the letters may be read through the aperture. The rays 
passing from the light (L) into the box through the aperture 
illuminate the opposite surface, and from this surface the 

7 



98 DISEASES OF TIIE EYE. [chap. iv. 



rays a, b, and others pass out again through the opening, 
and some of them fall into the observer's eye at E. 
But if, in order to make this box represent an eye, we 



Fig. 73. 

place a convex lens, n, of the proper strength, immediately 
within the aperture, all the rays passing into the box (Fig. 
74) from L are brought to a focus on its opposite side at m 
by the convex lens n, and, according to the law of conjugate 
foci, (chap i. § 16), all the rays passing out from the box meet 
again at the source of light (L), and hence none of them can 





r 

J-/ 


m 











* 



Fig. 74. 



be received by the eye (a) of the observer ; nor can this 
eye be placed in any position where it could receive any of 
these rays, for if it be placed anywhere between the aper- 
ture and L, it would cut off the light passing from L into 
the box. 

If the back of the box were further forward, the light 
would not be focussed on it, and the emergent rays would 
form parallel or conical divergent beams passing back to, and 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



99 



surrounding L. In the latter case, if an observer held his 
eye close beside the light, some of the divergent rays would 
enter it, and the letters would be visible. This explains the 
red pupil often seen in hypermetropia and aphakia. 

Helmholtz' s Ophthalmoscope. — If the eye of the observer could 
itself be made the source of light, the difficulty would be 
solved ; and, practically, this is what Helmholtz accomplished 
with his ophthalmoscope in the year 1851. The instrument he 
invented was composed of a number of small plates of glass 
(0, Fig. 75), from which light from L was reflected into the 



q "T 

ft . 'srf- . . - jjSr^^^S. -.___! 








s 





Fig. 75. 



eye (E), and thus the fundus of the latter illuminated. From 
m rays pass back again by the same path to the ophthalmo- 
scope, some being reflected back to L ; but some, passing 
through the ophthalmoscope, and falling into the observer's 
eye placed close behind the instrument at a, form in it an 
image of m. 

Modern Ophthalmoscope. — For the original ophthalmoscope 
of Helmholtz a concave mirror of 20 cm. focal length with 
a central opening has been substituted. This mirror (0, 
Fig. 76) throws convergent rays into the eye (E) ; and these, 
being made more convergent by the refracting media, cross in 
the vitreous humour, and light up part (a b) of the fundus. 
1" rom every point of this illuminated surface rays are 
reflected back again out of the eye. If the latter be emme- 



100 



DISEASES OF THE EYE. 



[CHAP. IV. 



tropic, the rays from any one point become parallel on leaving 
it ; and some of these parallel rays, passing through the 
aperture (c) of the ophthalmoscope, fall into the observer's 
eye, and, if it be emmetropic, are brought to a focus on its 
retina ; the rays from m at m, those from x at x, and those 




Fig. 76. 



from y at y — and thus an image of the part x m y is formed 
on the observer's retina. 

The foregoing method of examining with the ophthalmo- 
scope is called the Direct Method, or the Examination 
of the Upright Image. The light should be placed on 
the same side as the eye to be examined, it should be on a 
level with the eye, and sufficiently behind the patient to leave 
the eye in the shade. The observer uses his left eye for the 
patient's left eye, and his right for the patient's right eye, and 
by a slight inclination of his head he can get very close to 
the patient's eye without coming into contact with his face. 
By this method the various parts of the fundus are seen in 
their natural positions, but much enlarged. The magnification 
is about 15 diameters in Em., more in M. and less in H. ; 
and it is consequently very valuable for examining minute 
details. The area visible at one moment is, however, small, 
not much larger than the optic disc. 

It is necessary that the observer should approach his eye 
as close as he can to the eye under examination, in order 



CHAP. IV.] 



THE 0 PTITTIA L MO SCOPE. 



101 



to receive as much of the light coming out of it as possible, 
and also to obtain the largest possible field. 

Also the accommodation both of the observer's and of 
the patient's eye must be at rest, as otherwise the rays 
coming from the latter cannot form an image on the 
retina of the former, at least if both be emmetropic. 
If the patient exert his accommodation, the rays will, on 
leaving his eye, become convergent instead of parallel, and, 
falling into the observer's eye, will be brought to a focus 
in front of his retina. The same will happen if the 
observer exert his accommodation, and still more so if both 
patient and observer accommodate. The patient's accommoda- 
tion can be relaxed by making him gaze at the black wall 
behind the observer's head, or his accommodation may be 
paralysed with atropine. But atropine should never be used 
in adults unless absolutely necessary, owing to the incon- 
venience it causes the patient. 

Voluntary relaxation of the accommodation on the part of 
the observer is often a matter of much difficulty to beginners. 
With parallel optic axes our accommodation is relaxed ; 
therefore, when we want to relax our accommodation, we 
produce parallelism of our optic axes. This sounds easy 
enough ; yet, when the beginner approaches his eye close 
up to that of his patient, the knowledge that he is so close 
to the object he wishes to see renders the accomplishment 
of this parallelism and relaxation of accommodation very 
difficult to many. 

It can only be attained by practice, but it is assisted by 
the fact that the eye which is not in use gazes at the black 
wall behind the patient's head. 

The Indirect Method, or the Examination of the 

Inverted Image, is employed in order to obtain a more 
general view of the fundus than the direct method admits of. 

In addition to the ophthalmoscope, a convex glass — the object 
lens — (7, Fig. 77) of about 14 D is here used. The latter is 



102 



DISEASES OF TEE EYE 



[CHAP. IV. 



held at about its focal length from the eye (E) under 
examination, while the observer throws the light from the 
mirror through it into the eye. In passing through I 
the rays are made convergent, and this convergence is increased 
by the refracting media, so that the rays cross in the vitreous 
humour, and light up a portion of the fundus oculi. From any 
points (a and b) of this illuminated place pencils of rays pass out 




Fig. 77. 

again from the eye, and, becoming parallel, pass through I 
and are united by it at a b' ; and thus a real inverted 
image, magnified about 4 diameters, is formed of the part 
a b, which image may be seen by the observer whose eye is 
placed behind 0. The stronger the object lens (I) the more 
convergent will the rays from the examined eye be made ; and 
consequently the closer must a'b' be to each other, and the 
smaller and brighter must be the image formed. The weaker 
the object lens the larger and less brilliant is the image, and the 
less annoying to the observer are the reflexes from its surfaces. 

If the lens be held at its focal length from the cornea, 
and then withdrawn until its principal focus is further from 
the eye than the anterior focus of the latter, the im.age will 
remain unaltered in size in Em., will increase in size in M., 
and diminish in H. 

In examining by the indirect method, the observer first 
places the upper edge of the ophthalmoscope to his right 
supra-orbital margin, and, taking care that he is looking 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



103 



through the central opening of the mirror, he reflects the 
light of the lamp into the patient's eye at a distance of about 
50 cm. A red glare from the fundus will then be seen in the 
pupil. Keeping the pupil illuminated, the convex lens of 14 D, 
held between the forefinger and thumb of the observer's left 
hand, is brought up in front of the patient's eye, and kept 
there in the perpendicular position, the observer steadying this 
hand with the tip of the little finger on the patient's forehead. 
The object lens is now removed just far enough from the 
patient's eye to cause the margin of the pupil to disappear 
out of the observer's field of vision. The observer then ceases 




a b 
Fig. 78. 



to look into the eye, and fixes his gaze on the object lens 
when the inverted image of the fundus should at once become 
visible, if the observer accommodates for the proper distance 
— and will seem to be situated in the object lens, although 
it really is in the air somewhat this side of the lens. 

If, as is usually the case, the ophthalmoscope be held in 
the right hand, it is better to place the light on the patient's 
left, whichever eye be examined, as the observer's left arm 
will not then interfere with the light when the lens is 
held up before the patient's eye. 

The diagram (Fig. 78) serves to illustrate the effect of 
inversion of the image. The left eye is seen in the upright 
image at a, while the same eye is seen in the inverted image 



101 



DISEASES OF THE EYE. 



[chap. IV. 



at b. In the diagram the two images are of the same size 
for- the sake of convenience ; although, of course, in reality 
the upright image is much larger than the inverted image. 
Moreover, it should not be supposed that nearly the whole 
fundus oculi, as here represented, can be taken in at one 
view with the ophthalmoscope. The portion visible with the 
ophthalmoscope at one moment, even in the inverted image, 
is small ; so that it is necessary to examine the different 
regions in detail, in order to become acquainted with the 
condition of the whole of the fundus. 

The reflex from the surface of the cornea gives a good deal 
of annoyance to every beginner. It cannot be done away 
with ; but, as it moves in the opposite direction to a motion 
of the object lens, it is possible to see past it. The reflections 
from the convex object-lens are also extremely annoying, but 
may be removed to a great extent from the line of sight by a 
slight rotation of the lens on its axis. If a very high object 
lens (say + 20 D) be used, the reflections from it are more 
disturbing than from a lower number (say -f 14 D). 

To examine the Optic Nerve (or Optic Disc) the observer sits 
in front of the patient, and directs him to turn his eye some- 
what to the nasal side, and slightly upwards ; because the 
papilla, or disc, is situated about 15° to the inner side of 
the posterior pole of the eye, and about 3° above it. For 
instance, if the left eye be examined the patient is to direct 
his gaze, (without turning his head,) to his right and a 
little upwards, say towards the observer's left ear. It is well 
always to seek out the optic papilla in the first instance, not 
only because it is such an important part of the fundus oculi, 
but also because, examining from it towards the periphery, 
we are the better able to determine the locality of any 
pathological alteration. 

Should the patient not direct his gaze in such a way as to 
enable the observer to see the optic disc or other desired 
region, it may be brought into view either by a motion of the 



CHAP IV.] 



THE OP II Til. A L MO SCOPE. 



105 



observer's head in the opposite direction, or by a motion of 
the convex lens in the same direction, or by a combination 
of these measures. When the disc is opposite the observer's 
eye, the pupillary reflex is seen to become paler or even 
white, and the corneal image of the light will occupy the 
junction of the middle and outer thirds of the horizontal 
diameter of the cornea. 

The Macula Lutea should then be examined. It may be 
seen by directing the patient to look straight at the hole of 
the ophthalmoscopic mirror, for it will then correspond with 
the macula lutea of the observer's eye. It is more readily 
seen in the inverted than in the upright image ; but its 
examination is often very difficult, owing to contraction of the 
pupil produced by the strong light falling on so sensitive a 
portion of the retina, and by the reflections from the surfaces 
of the cornea and crystalline lens, which fill the area of this 
contracted pupil. It is therefore a better plan to direct the 
patient to look somewhat to the side of the eye under examina- 
tion — e.g., to the right side of the observer's forehead, if the 
left eye be under examination, and then by motions of the 
convex lens to bring the macula lutea into view. 

After this the Periphery of the Fundus in every direction is 
to be examined by making the patient look upwards, down- 
wards, to the right, to the left, etc. 

The indirect method possesses the following advantages: — 
It gives a large field in which it is possible to rapidly locate 
the position of a lesion, it can be used no matter what the 
error of refraction may be, and it is not necessary to approach 
close to the patient's face. 

Estimation of the Refraction by Aid of the 
Ophthalmoscope. 

Egtimation of the Refraction ly the Inverted Method. — The position 
of the inverted image, in other words its distance from the lens used, 
depends Qn the strength of the lens, its distance from the eye, and 



106 DISEASES OF THE EYE. [chap. iv. 



on the refraction of the eye. If the number of the lens and its distance 
be fixed, the refraction alone causes the alteration in the position of 
the inverted image. In Em., the emerging rays being parallel, the 
image is formed at the focus of the lens; in M., the rays being con- 
vergent, the image is closer to the lens ; and in H. it is further away, 
owing to the divergence of the rays coming out of the eye. The 
methods of measuring the refraction which are based on these 
principles have not, however, come into general practical use. 

By the Direct Method at a distance of about 50 cm. from 
the observed eye into which light from the ophthalmoscope 
mirror is thrown, the observer will be able to make the 
qualitative diagnosis of the refraction. If he can see some of 
the details of the fundus, the eye is either myopic or hyperme- 




Fig. 79. 

tropic; but if it be emmetropic, or have M. of less than 2 D, 
he will be unable to see any detail. The explanation of this 
is that, in myopia, the rays coming out of the eye form an in- 
verted image at the far point of the eye in the air, and this 
image can be seen by the observer who accommodates his eye 
for that point. In hypermetropia, the rays coming out diver- 
gently from the eye pass into the observer's eye, and, by an 
effort of accommodation on his part, he will see an upright 
image of the portion of the patient's fundus oculi from which 
they come. But in emmetropia, or low M., inasmuch as the 
rays come out either parallel or very slightly convergent, 
those from any two points (to, n, Fig. 79) at a short distance 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



107 



from each other in the fundus on emerging from the eye 
diverge quickly from each other, and the observer a little way 
off (at A) receives none of them into his eyes, or obtains only 
an indistinct image or red glare. If he go very close to the 
eye he can see details. 

If, on the observer moving his Lead from side to side, the 




Fig. 80. — Apparent motion of fundus with the observer in H. 

vessels, 'etc., of the observed fundus move with him, the case 
is one of hypermetropia, if against him it is a case of myopia. 
In H. (Fig. 80) the observer at 0 sees an erect image of the 
fundus at F behind the plane of the pupil, P, and it appears 
to be situated at A ; on moving the head to 0', the line of 




Fig. 81. — Apparent motion of fundus against the observer in M. 

vision is 0 F, and F appears to be at A'. In myopia (Fig. 
81) the image is an inverted one lying in front of the 
plane of the pupil at F, and when the observer changes to 
O' the image appears to be in the pupil at A'. 

*For the quantitative determination of ametropia a refrac- 
tion ophthalmoscope is required. This instrument is provided 
with a number of convex and concave lenses cupable of being 



108 



DISEASES OF 'I HE EYE. 



[chap. IV. 



brought into position behind the sight-hole in rapid succession 
by a simple mechanism ; and also with a tilted mirror which 
avoids the necessity of holding the ophthalmoscope in an 
oblique position, and thus the lenses are maintained in a 
position at right angles to the visual axis of the observer. 
The direct method, close up to the patient's eye, is employed. 

It is necessary, in the first instance, that the observer be 
acquainted with the nature of his own refraction. 

*If the Observer be Emmetropic he can see the fundus oculi 
of an emmetrope in the upright image without any lens, 
provided he go close enough, as the parallel rays coming 
from the examined eye will be focussed on his retina, because 
his eye is adapted for parallel rays. 

In order to see the fundus oculi of a hypermetrope without 
any effort of accommodation, he must place such a convex lens 
behind his ophthalmoscope as will render the divergent rays 
coming from the patient's eye parallel before they pass into 
his eye. This lens is the measure of the patient's hyper- 
metropia, because it shows how many dioptres the eye wants 
of being emmetropic. The lens which makes the divergent 
rays coming from the patient's retina parallel, would also 
give to parallel rays passing into the eye such convergence 
that they would meet on the retina — i.e., it would also correct 
the hypermetropia if the patient were examined with test- 
types and glasses (p. 65). (See Fig. 55.) 

The emmetropic observer can of course see the fundus oculi 
of a hypermetrope by the direct method without the correcting 
glass, if he use his accommodation to overcome the divergence 
of the rays coming from the observed eye, and this is usually 
the case in the lower degrees of hypermetropia. The observer 
generally relaxes his accommodation according as he sub- 
stitutes convex lenses for it, until he reaches the strongest lens 
with which he can distinctly see the fundus. This is the 
correcting lens. 

To see the fundus oculi of a myope, the emmetropic observer 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



109 



must place a concave glass behind his ophthalmoscope, in order 
that the convergent rays coming from the observed eye may 
be made parallel before they pass into his eye ; and the lowest 
concave lens which enables him to see the fundus oculi dis- 
tinctly is the measure of the myopia (see p. 49), as showing 
by how many dioptres it is in excess of emmetropia. 

The emmetropic observer cannot possibly see the fundus 
oculi of a myope without the correcting glass, as the rays are 
brought tOi a focus in front of his retina, and if he use his 
accommodation he merely makes them still more convergent. 
But, by means of an effort of his accommodation he can see 
the myopic fundus with a lens which over-corrects the myopia, 
and hence the importance of selecting the weakest concave 
glass with which the fundus is distinctly seen. 

If the observer be ametropic, he may either correct his 
ameti'opia by wearing the suitable lens, and then proceed as 
though he were emmetropic, or else, and which is perhaps 
the better plan, he must allow for the amount of his ame- 
tropia. 

For example : — 

*The Hypermetropic Observer of say 3 D requires a -f lens 
of 3 D in order to see an emmetropic fundus oculi, this lens 
going altogether to correct his own defect. If in order to 
examine the fundus of another eye he require a -f- lens of 
6 D, the examined eye must be hypermetropic 3 D, the other 
3 D going to correct the observer's H. If he be able to 
see the fundus oculi under observation without any lens, it 
shows that the eye has an excess of refraction corresponding 
to the want of refraction in his own eye — that is to say, 
it is myopic 3 D. If he require a concave 2 D, his want 
of refraction — his hypermetropia — is not enough by that 
number of dioptres, and he has to do with an eye which is 
myopic 5 D (3 D + 2 D). Again, if he can see the fundus 
distinctly with a + lens, say -f- TO, which is less than his 
own correcting glass, this shows that the eye he is examining 



110 



DISEASES OF THE EYE. 



[CHAP. IV. 



is myopic, but myopic to a lesser degree— in this instance by 
1 D — than he himself is hypermetropic, and the examined 
eyo here would be M. 2-0 D (i.e., 3-0 — 1-0). 

If the Observer be myopic the same method of reasoning 
applies. 

*The Existence and Degree of Astigmatism may be Determined 
with the Ophthalmoscope. — We know that astigmatism is present, 
if in the upright image we see the upper and lower margins 
of the disc and the horizontal vessels well defined, while the 
lateral margins and the vertical vessels are blurred, or vice 
versd. Again, we know that astigmatism is present if in com- 
paring the shape of the optic disc in the upright and inverted 
images, we find it to be an oval with its long axis perpendicular 
in the former, and with its long axis horizontal in the latter, 
showing that the refracting media are more powerful in the 
vertical than in the horizontal meridian. 

We may ascertain the kind and degree of astigmatism as 
follows : — 

If in the upright image with relaxed accommodation, we 
can see the retinal vessels in one meridian distinctly, while 
in order to see those in the opposite meridian a concave or 
convex lens behind the ophthalmoscope is required, we know 
that the case is one of simple myopic or hypermetropic astigma- 
tism ; the emmetropic meridian being that at right angles to 
the vessels 1 seen without any lens, and the number of the lens 
indicating the amount of ametropia in the other meridian. 

If, in the two principal meridians, two concave lenses or 
two convex lenses of different strength be required, we have 
to deal with a case of compound astigmatism, myopic or 
hypermetropic ; the greatest error of refraction being in the 
meridian at right angles to that one, the vessels of which ai-e 
made distinct by the strongest lens. 

If a concave lens be required to bring into distinct view the 

1 The vessels may be regarded as lines, and the explanation given on 
pp. 74 and 75 applies to them also. 



chap. iv.] THE OPHTHALMOSCOPE. Ill 



vessels in one meridian, while a convex lens is required for 
the opposite meridian, the case is one of mixed astigmatism. 
Myopia exists in the meridian at right angles to that in which 
the vessels are brought into view by the concave lens, and 
hypermetropia exists in the opposite meridian. 

Retinoscopy. 

Retinoscopy, or the Shadow Test, is the most useful 
method for determining the refraction by the ophthalmo- 
scope. It consists in illuminating the eye with the plane 
or concave mirror at a distance of a little over a metre, or 
more, and then by moving the light into different positions by 
rotation of the mirror round an axis lying in its own plane, 
the observer noting on which side of the illuminated pupil 
the shadow appears, and in which direction it moves across 
the pupil. 

Theory of Retinoscopy. — In the explanation which follows, the con- 




Fig. 82. — Retinoscopy with concave mirror. Shows that the real 
movement of the retinal image is the same in all conditions of 
refraction. 1. Motion of mirror, or of light area on patient's face. 
2. Motion of aerial image produced by mirror (immediate source 
of light). 3. Real motion of retinal image of light. 



cave mirror is supposed to be used. In Fig. 82, rays from the light, 0, 
placed at the side of the patient's head, strike the mirror, A, which 
forms an inverted aerial image, A', as explained at the beginning of 



DISEASES OF THE EYE. [chap. IV. 



this chapter. This image is now the immediate source of light, rays 
from which, entering the eye, are made to converge toward their con- 
jugate focus, /, on the secondary axis, AN/, passing through the nodal 
point, N. If the retina be at M', or in other words, if the eye be myopic, 
with its far point at A', a distinct and bright image of the light, A 
will be formed on the retina at/. Iu any other condition of refraction 
such as emmetropia, E., hypermetropia, H., or any higher degree of 
myopia, M., a circle of diffusion, c d, is formed by each point of light, 
and a blurred image is the result; so that the area of illumination 
is less bright, and its boundary less denned. The further the retina 
is from / the less will be the brightness and the definition of the 
margin of the illuminated area. 

Now let the mirror be rotated from A to B, the movement of the 
light area, surrounding the eye, on the patient's face will, of course, take 
the same direction, indicated by the arrow 1. As explained at the 
beginning of this chapter, the immediate source of light will move 
to B', shown by arrow 2, and its image will be formed, more or less 
distinctly, on the retina, at the point at which it is intersected bythe 
secondary axis B N ft. The retinal image, therefore, will move in the 
direction of arrow 3, from a to b, and this motion, as the figure shows, 
is the same in all positions of the retina. The real motion of the retinal 
image of the light in the observed eye is therefore independent of the 
refraction of the eye, and is in a direction contrary to that of the 
immediate source of light, and also against the motion of the concave 
mirror. 

The observer cannot, however, see directly what is actually taking 
place on the retina of the observed eye, since he can only examine it 
through its refractive media. It remains, therefore, to determine the 
effect of the refraction of the observed eye on the motion as it appears 
to the observer ; this may be called the apparent movement. What the 
observer sees is the image, real or virtual, formed by the observed 
eye, at its conjugate focus or punctum remotum, and therefore the 
apparent movement will depend on the position of the far point. 

In H (Fig. SS) the immediate source of light, A, illuminates a portion 
of the retina at a. The rays c, f emerging from this point diverge, 
and entering the observer's eye seem to him to come from a, the far 
point of the hypermetropic eye. When, by reason of a rotation of the 
mirror to B, the light moves to B', its retinal image b, seems to be at 
/3. The illuminated area seems therefore to have moved in the direc- 
tion of arrow 4 ; that is, against the motion of the mirror (arrow 1). 

In Em. similarly, the emergent rays are parallel, and the image is 
projected by the observer to a position behind the eye under examina- 
tion. Stated simply, in both cases an erect image of the fundus is seen, 
therefore no reversal of the rays takes place between the eye of the 
observer and that of the person under observation ; and consequently, 



CHAP. IV.] 



THE OPM tS. I LMOSCOPE. 



113 



the apparent motion is the same as the real. As the light moves 
from a to j3 and so passes on, the pupil will first appear to become 
darkened above, and the shadow will move' across it as shown in the 
circle P. 

In Myopia, on the other hand (Fig. 84), the rays from the illuminated 
area a converge to form an inverted image at o, the far point of the 




Fig. 83. Retinoscopy.with concave mirror, in hypermetropia. 1. Motion 
of mirror. 2. Motion of immediate source of light. 3. Eeal motion 
of retinal image. 4. Apparent motion of retinal image. 



eye, situated on the secondary axis AN«. When the immediate source 
of light moves from A' to B', the apparent movement is from o to ^ 




Fig. 84. — Retinoscopy with concave mirror in Myopia. Numbers 

as in Fig. 83. 



In this case a reversal of the relative position of the rays takes place, 
before they enter the observer's eye ; the upper rays become the lower 
and vice verm. Hence this is sometimes called the point of reversal. 
In this case the darkness will appear first at the lower edge of the 
pupil, and will travel upwards as indicated in the circle P, that is to 
say, in the same direction as arrow 1, until the movement of the 
concave minor. 

8 



iu 



DISEASES OF THE EYE. 



[chap. IV 



The abovo explanation only holds good in myopia, wben, as in the 
figure, the far point of the eye under observation lies in front of the 
observer's eye. If, however, the far point be situated further back 
than the observer's eye, the rays will not have met to form the inverted 
image, but will enter his eye retaining the relative positions which they 
bore to each other on emerging from the eye under observation ; conse- 
quently the observer will see an erect image of the illuminated area, 
and the movement will be as in H. and Em., namely, against the 
concave mirror. It is obvious, that the lower the degree of myopia 
the further away the observer must be in order to see the reversal 
of the movement. 

An error of refraction in the observer's eye does not influence the 
apparent movement, but mereiy renders the appearance more or less 
distinct to him. It should also be stated, that as the observer accom- 
modates for the patient's pupil, and not for the far point of the retina 
of the patient, the image seen is always more or less diffuse. 

Retinoscojnj with the plane mirror.— The immediate source of light 
in the case of a plane mirror is a virtual upright image behind the 
mirror (Fig. 71). It moves in the opposite direction to the motion 
of the mirror, and not with it, as in the case of the concave mirror. 
Hence the real movement of the retinal image in the patient's eye will 
be with the mirror. The appareut movement will, therefore, be the 
same ; that is, with the mirror, in Em., H., and in low M., where the point 
of reversal is further away than the observer. In higher degrees of M., 
with the point of reversal nearer than the observer, the real motion 
will be reversed, and hence the apparent motion will be against the 
motion of the mirror. 

Degree of illumination, form, and rate of movement of the shadow. — 
As shown in Fig. 82, when the retina is at the conjugate focus of the 
immediate source of light, the illumination is at its greatest. The 
further away the retina is from the conjugate focus, that is to say, the 
higher the H. or M., the larger must be the area over which the light 
is spread, and therefore the more defective the illumination becomes, 
and the less defined and the fainter is the edge of the shadow. 

The higher the error of refraction, the nearer to the eye is the far 
point, and the smaller is the remote image ; but with the smaller image 
a larger field is obtained, and more of the circular edge of the shadow- 
is seen ; hence, the latter appears crescentic. In the lower degrees of 
ametropia and more especially in Em., the magnification is much 
greater and the field is smaller. Therefore, a small portion only of the 
large circular edge is visible, causing the shadow to appear less cres- 
centic and more linear. 

The apparent rate of movement depends more on the degree of 
magnification of the remote image, than on the real rate of movement 
of the retinal image. The less the magnification the slower the move- 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



115 



ment appears, for instance in Figs. S3 and 84, if the far point were in 
each case at c, the light would have to travel only from d to c, instead 
of from o to j3, with the same rotation of the mirror. At c, therefore, 
it would appear to travel a shorter distance in the same time, and 
would therefore appear to move slower. The higher the ametropia, 
then, the slower appears to be the movement of the shadow. 

Practice of Retinoscopy with the Concave Mirror.— 

The examination is conducted in the dark room. The light 
is placed at the side of, or above the patient's head, behind 
the level of his eye so that the latter may be in the 
shadow. If the concave mirror be used, the observer 
sits at a distance of 1*25 m. in front of the patient. The 
focal length of the mirror should be about 22 cm., and 
the diameter of the sight hole about 3 mm. The observer 
should correct any error in his refraction. The light is 
then thrown into the patient's eye, near the region of the 
macula lutea, but not on it, unless the pupil be dilated by 
atropine, otherwise the pupil becomes too small and the 
red reflex too faint. The observer accommodates for the 
pupil, and rotating the ophthalmoscope, usually in the 
horizontal and vertical meridians, he observes the shadow 
at the circumference of the pupil. When the mirror is 
rotated — say, in the horizontal meridian — the edge of the 
shadow will be vertical, it will move horizontally, that is 
at right angles to its edge, and it will indicate the refraction 
of the horizontal meridian. If the movement of the shadow 
l>e with the movement of the mirror, or with the light on the 
patient's face, myopia is present ; if it move against the 
mirror, Em., H., or M. of less than 1 D is present. 

The reason why the shadow is against the mirror in cases 
of less than 1 D is that, in M. of 1 D, the inverted image 
or point of reversal of the emerging rays, is situated at 
the far point of the patient's eye, namely 1 m. in front of 
the patient, and the observer being 25 cm. further away sees 
this inverted image. But if the myopia be less than 1 D, 
the far point, or point of reversal, lies behind the observer's 



116 



DISEASES OF THE EYE 



[chap. IV. 



head, and he now sees an erect image as in Em. or H., and 
the apparent movement is then the same as in Em. or H., 
namely against the mirror. 

In order to estimate the error of refraction, a trial 
spectacle-frame is put on the patient's face. If the 
shadow move with the mirror, we know at once the eye is 
myopic. To find the degree of myopia the observer puts a 
low concave-glass (say — ID) into the frame ; and if the 
shadow still move with the mirror, he puts in a higher 
number (say — 1-5 D), and so on until he comes to a glass 
which makes the image move against the mirror. If this 
be — 3 D, the myopia is 3 D. It might be supposed, as the 
shadow now moves against the mirror, that this glass over- 
corrects the myopia ; but this is not so, because, as already 
explained, when the myopia is very low the image is formed 
close to the observer's eye, or behind his head, and he conse- 
quently gets a shadow moving against the mirror, although 
low myopia, and not emmetropia, is present. Consequently, 
— 0 - 5 D, or — 1 D, has to be added on to the lens, which 
gives the effect of no distinct shadow ; or rather, by the 
above plan, it is not deducted from the lowest lens, which 
makes the shadow move against the mirror. 

If the shadow move against the mirror, we have to de- 
termine whether the eye is emmetropic, hypermetropic, or 
slightly myopic. Should the illumination be bright, and the 
shadow well defined, the eye is emmetropic, or not far removed 
from it ; and if the shadow be ill defined and crescentic, we 
may feel sure the eye is highly hypermetropic. We first put 
on -J- 1 D, and if the motion be still against the mirror, the 
case is one of hypermetropia, and higher numbers are at once 
proceeded to, until that one is reached which causes the 
shadow to move with the mirror. The measure of the hyper- 
metropia is 1 D less than the glass so found, for it has 
evidently over-corrected the defect, having made the eye 1 D 
myopic. 



CHAP. IV.] 



THE OPHTHA LMUSCOPE. 



117 



If, however, on putting on -f- 1 D we find the shadow to 
move with the mirror, we change it for + 0*5 D ; and if 
still the motion be with the mirror, the eye is, beyond doubt, 
slightly myopic, — 0 - 5 D or so. But if with -f 1 D the 
shadow move with the mirror, while with -f- 0 - 5 it continue 
to move against it, the eye is emmetropic. 

In astigmatism, the light being differently focussed in two 
meridians at right angles to each other, and being drawn 
out into a line or oval of diffusion, causes the illuminated 
area to appear like a band. The boundary of the shadow 
therefore is more of a straight line than 
a crrcle. If the axes of the astigmatism 
be oblique, the edge of the shadow will 
lie in one of the meridians and the 
movement will take place in the 
other — according to the direction of 
the rotation of the mirror. Even if 
the mirror be not rotated in the 
direction of the meridian of greatest 
or least refraction, the edge of the 
shadow will nevertheless lie in the 
direction of one of these meridians, 
namely in that which is nearest to 
the axis of rotation, and will appear 
to move in the meridian at right 
angles to it. This is due to an 
optical illusion explained by Fig. 85. 

It may be found that in opposite meridians there is a 
difference in the motion of the shadow, and this indicates 
the presence of astigmatism. When the difference is one 
merely of rapidity of motion, or of intensity of illumination 
and shadow, it is either simple hypermetropic or compound 
astigmatism. But if in the two meridians there be a differ- 
ence in the direction of the motion, then it is simple myopic 
or mixed astigmatism. 




Fig. 85.— If (TD.be 
moved behind the 
circle in the direction 
of E, its obliquity 
being preserved, it 
will appear to a per- 
son who sees only the 
portion inside the 
circle, to move in 
direction A. 



118 



DISEASES OF THE EYE. 



[CHAP. IV. 



In some rare cases the refraction is different at opposite 
sides of the pupil, and a double shadow is seen. These 
shadows move simultaneously in opposite directions ; that 
is, towards or away from each other, like the blades of a 
scissors, and hence the condition is known as " scissors move- 
ment." In conical cornea, an irregular or triangular shadow 
is seen, with its apex near the centre of the pupil. It 
rotates round its apex with the movements of the mirror. 
In irregular astigmatism, the shadow appears broken up 
very irregularly, and different portions of it move in various 
directions. 

The best method of ascertaining the degree of astigmatism 
and its correcting glass is to correct each of the principal 
meridians separately with spherical lenses. In compound 
astigmatism, the difference between the two lenses found in- 
dicates the degree of astigmatism, and also the cylindrical 
lens which, combined with the correcting spherical lens for 
the least ametropic meridian, is required to neutralise the 
defect. In mixed astigmatism, the addition of the two 
numbers gives the cylindrical lens, while one or other of 
them, usually the — D, is used as the spherical lens. 

Retinoscopy with the plane mirror. — As explained on 
p. 96, the immediate source of light moves in a direction the 
reverse of that which is produced by the concave mirror ; 
therefore, the apparent movement is with the mirror in 
H., Em., or low M., and against it in the other degrees of 
M. It will be noticed that this is the same as the apparent 
movement of the vessels when the observer moves his head 
(p. 107). The advantage of the plane mirror is, that the 
observer can stand further away from the patient, and thus 
diminish the error of observation. If, for example, the 
distance be a little more than 4 m. when the shadow 
moves with the mirror, the observer knows, if M. be present, 
it must be less than 0-25 D. He has still to decide whether 
this indicates E. or H. He does so by putting a low + lens' 



CHAP. IV.] 



THE OPHTHALMOSCOPE. 



119 



(say + 0-25) before the patient's eye, and if then, standing 
at a distance of 4 metres, the motion be altered by this glass 
to one against the mirror, he knows that the eye has not a 
hypermetropia of 0'25 D, consequently that it is emmetropic. 
But if this lens does not at that distance cause a change in 
the motion of the shadow as originally obtained, the eye 
must be hypermetropic to at least the extent of 0 - 25 D ; 
and, in order to ascertain how much more of H. than this 
may be present, it is now only necessary to continue increasing 
the strength of the lens in front of the patient's eye, until 
one is reached which, at 4 metres from the eye, produces 
the myopic motion. The observer knows that he has now 
slightly over-corrected the hypermetropia of the eye, and 
that the next lens lower is its measure. 

A plane mirror of 4 cm. diameter, and of which the 
sight-hole is 4 mm. in diameter, is the pleasantest to use 
for retinoscopy. 

Detection of Opacities in the Refractive Media by 

the Ophthalmoscope. — Opacities in the refractive media 
can be best detected with the ophthalmoscope by the 
direct method. All opacities look black in the red pupil, 
because they intercept the light returning from the 
illuminated fundus. 

Two methods of examination are employed. In the first 
the eye is examined at a distance of about 30 cm. ; and 
the patient is directed to move the eye in different directions, 
in order to bring any peripheral opacities into view and also 
to localise them. Movable opacities must lie in the fluid 
media. They are almost always in the vitreous humour, and 
can be seen to float to and fro when the eye comes to rest. 
Fixed opacities move with the eye, and lie in the cornea or 
lens, or sometimes in the vitreous. Fig. 86 illustrates the 
apparent displacement of an opacity in the pupil according 
to its position in the media. When the eye of the observer 0 
is opposite the pupil, the opacities 1 to 4 lying on the axis 



120 



DISEASES OF THE EYE. 



[chap. IV. 



appear as one point in the centre of the patient's pupil (shown 
by P). When the eye is rotated upwards, or the observer 
moves downwards, 2, which is on the anterior surface of 
the lens, in the plane of the pupil, will still appear to be 
in the same position, while 1, seen in the direction a b, 




Fig. 86. — Apparent position in the pupil of opacities of the media 
when the observer alters his point of view. 

will seem to be displaced upwards, and 3 and 4 downwards, 
the relative positions being as indicated in the circle at P'. 

The second and more delicate method of detecting opacities, 
consists in examining the eye close up with a convex lens of 
20 D, behind the sight hole of the mirror. Very tine opacities 
can be seen in this way, such as very delicate punctate 
deposits on the cornea. Focussing for different levels can be 
accomplished by approaching closer for deeper opacities, or by 
using gradually weaker lenses. Too stroDg illumination 
interferes with the perception of faint opacities, hence the 
plane mirror serves better for this purpose than the concave. 

THE NORMAL FUNDUS OCULI AS SEEN 
WITH THE OPHTHALMOSCOPE. 

The Optic Papilla, or Optic Disc. — This is the first object 

to be sought for by the observer. It presents the appearance of 
a pale pink disc, somewhat oval in shape, its long axis being 



chap. IV.] THE NORMAL FUNDUS 0CUL1 



121 



vertical. Occasionally the long axis lies horizontally, and 
sometimes the papilla is circular. The papilla is generally 
surrounded by a white ring, more or less complete, called the 
sclerotic ring, and often, outside this again, by a more or less 
complete black line, the chorioidal ring (Fig. 87). The sclerotic 
ring is duo to the chorioidal margin not coming quite up to the 
margin of the papilla, the foramen in the chorioid for the 
passage of the optic nerve fibres being somewhat larger than 
that in the sclerotic, and consequently a narrow edging of the 
white sclerotic is exposed. The chorioidal ring is the result of 
a hyper-development of pigment 
at the margin of the chorioidal 
foramen. The complexion of 
the optic disc results from the 
pink hue derived from its fine 
capillary vessels, combined with 
the whiteness of the lamina 
cribrosa, and the bluish shade 
of the nerve fibres. It is fre- 
quently not equal all over, but 
is paler on the outer side, where 
the margin is more defined, and 
where the nerve fibres are often 
fewer than on the inner side. 
The apparent colour of the 

papilla depends also upon the complexion of the rest of the 
fundus. If the latter be highly pigmented, the papilla appears 
pale in contrast ; while, if there be but little pigment in the 
chorioid, the papilla may appear very pink. The complexion 
of every normal papilla is not identical, and care must be 
taken not to make the diagnosis " Hypersemia of the papilla " 
where merely a high physiological complexion is present. The 
upper and lower margins of the papilla are often, especially in 
young people, a little indistinct, and show a delicate striation 
by the direct method of examination. This may be greatly 




Fig. 87. — Normal optic disc, 
showing a physiological cup, 
scleral and chorioidal rings, 
and cilio-retinal vessel (c). 



122 



DISEASES OF THE EYE. 



[chap, iv 



exaggerated in hypermetropes, and has in them been some- 
times erroneously taken for optic neuritis. 

A physiological excavation of the optic papilla is often met 
with (Fig. 87). It is either on the temporal side or in the 
centre of the papilla, and can be recognised from the parallax 1 
which may be produced, and from the paleness of this portion 
of the papilla. When the excavation is very deep, one may 
sometimes observe the lamina cribrosa in the form of grey 
spots (the nerve fibres) surrounded by white lines (the fibrous 
tissue of the lamina). 

A physiological excavation differs from a pathological 
excavation, in that it does not reach the margin of 
the papilla all round. It is caused by the crowding over 
of the nerve fibres to the inner side of the papilla. Yet 
sometimes, a healthy optic papilla will be met with, in which 
the excavation apparently reaches the margin all round. 
Doubtless, in such cases, the thickness of the translucent 
nerve-fibre layer alone it is, which is interposed between the 
sclerotic margin and the margin of the cup all round. 

The Normal Retina is so translucent that it cannot 
be seen ; or at most, a shimmering reflection or shot-silk 
appearance is obtained from it, particularly about the region 
of the yellow spot and along the vessels, but also towards 
the equator of the eye, and especially in dark eyes, and in 
young people. 

A peculiar, but physiological, appearance known as opaque 
nerve fibres is occasionally seen. It is produced by some 
of the nerve fibres forming the internal layer of the retina 
regaining the medullary sheath on the distal aspect of the 
lamina cribrosa, or near the margin of the papilla, which 
they had lost in the optic nerve just before entering the 
lamina cribrosa ; the rule being that the nerve fibres lose 
their medullary sheath at the latter place definitely, and 



1 For explanation of the parallax gee chap. xiii. 



chap. iv.] THE NORMAL FUNDUS OCULI. 



123 



enter the retina as axis cylinders only, and hence are quite 
translucent. Instead of that, in these cases their fibres 
refiect the light strongly, giving the effect of an intensely 
white spot, commencing at the disc, extending more or 
less into the surrounding retina, and terminating in a 
brushlike extremity. This appearance is constant in the 
rabbit's eye. 

The Macula Lutea is generally seen as a bright oval ring 
with its long axis horizontal, this ring being probably a reflex 
from the surface of the retina. It is remarkable that this 
halo is not visible with the direct method of examination — 
a fact due probably to the illumination being much weaker 
than with the indirect method. The area inside the ring is 
of a deeper red than the rest of the fundus, and at its very 
centre there is an intensely red point, the fovea centralis. 
This ring is not seen in old people. 

The General Fundus Oculi surrounding the optic papilla 

and macula lutea varies a good deal in appearance according 
to the amount of pigment contained in the chorioid and in the 
pigment-epithelium layer of the retina. 1. If there be an 
abundant supply of pigment in each of these positions, the 
chorioidal vessels are greatly hidden from view, and the effect 
is that of a very dark red fundus. 2. If there be but little 
pigment in the pigment-epithelium layer, the larger chorioidal 
vessels may be visible, and the fundus may appear to be 
divided up into dark islands surrounded by red lines. 3. If 
the individual be a blonde, there is little pigment either in the 
pigment-epithelium layer or in the chorioid, and the fundus is 
seen of a very bright red colour, the chorioidal vessels down 
to their fine ramifications being discernible. In albinos even 
the chorioidal capillaries may be seen. 

The Retinal Vessels. — The arteries are recognised as 
thin bright red lines running a rather straight course, in the 
centre of each of which is a light-streak. As to the cause of 
this light-streak there is considerable divergence of opinion. 



124 



DISEASES OF THE EYE. 



[chai\ IV. 



Some attribute it to reflection from the coats of the vessel, or 
from the surface of the blood column ; while others believe 
that the light is reflected from the fundus through the vessel, 
which then acts as a very strong cylindrical lens. This light- 
streak divides the vessel into two red lines. The veins are 
darker, wider, and more tortuous in their course than the 




Fig. 88 (^6 reef e and, Scemisch). 

a.ii.s., Art. nas. sup. ; a.n.i., Art. nas. inf. ; a.t.s., a.t L, A. temp. sup. and inf. ; 
v.n.e., v.n.i., Yen. nas. sup. and inf. ; v.t.s., v.t.i., Yen. temp. sup. and inf. ; a.vi.e., 
v.m.e., Art. and ven. median ; a.m., v.m , Art. and ven. ruacularis. 

arteries, and, their coats not being so tense, the light -streak 
on them is very much fainter. 

On reaching the level of the nerve-fibre layer of the retina 
the central artery and vein divide into a principal upper and 
lower branch. This first branching often takes place earlier 
in the vein than in the artery, and the former may even branch 



chap, iv.] THE NORMAL FUNDUS OCULT. 



125 



before appearing on the papilla, as in Fig. 88. The second 
branching may take place in the nerve itself ; and when this 
occurs it will appear as though four arteries and four veins 
sprang from the optic papilla; but more usually this branching 
occurs on the papilla, as in Fig. 88. The vessels produced by 
this second branching pass respectively towards the median 
and temporal side of the retina, and are termed by Magnus 
the Art. and Ven. nasalis and temporalis sup. and inf. (vide 
Fig. 88). The temporal branches run in a radial direction 
towards the anterior part of the retina. A small horizontal 
branch, the Art. and Ven. mediana of Magnus, from the first 
principal branches is found passing towards the nasal side 
of the retina. The temporal branches do not run in a 
horizontal direction, but make a detour round the macula 
lutea, sending fine branches towards the latter. Two or three 
minute vessels from principal branches run directly from the 
papilla towards the macula lutea, and around the macula 
lutea a circle of very fine capillary vessels is formed which 
cannot be distinguished with the ophthalmoscope ; but no 
vessels run to, or cross over, the fovea centralis itself. The 
retinal arteries do not anastomose, nor do the larger retinal 
veins. The small retinal veins have some slight anastomoses 
near the ora serrata. Occasionally a vessel emerges near the 
margin of the disc, usually at the temporal side. It arises from 
the ciliary vessels, and is hence called a cilio-retinal vessel 
(Fig. 87). 

No pulsation of the arteries is observable in the normal 
eye. In the larger veins near or on the optic papilla, or 
more usually just at their point of exit, a pulsation may 
sometimes be seen. This venous pulsation is due to the 
following sequence of events : Systole of the heart ; diastole 
of, and high tension in, the retinal arteries ; consequent in- 
creased pressure in the vitreous humour ; communication of 
this to the outside of the walls of the retinal veins, impeding 
the flow of blood through them, especially in their larger 



120 



DISEASES OF THE EYE. 



[chap. IV. 



trunks, which offer little resistance, or at their exit from the 
eye, where they offer the least resistance ; and in this way 
the veins are emptied — the blood gradually coming on from 
the capillaries overcomes the resistance, and the veins are 
for a moment refilled. The phenomenon can be most readily 
observed, if the normal tension of the globe be slightly 
increased by pressure of a finger during the ophthalmoscopic 
examination. 



CHAPTER V. 



DISEASES OF THE CONJUNCTIVA. 

The Conjunctiva, or Conjunctival Sac, consists of three 
portions : the palpebral, lining the inside of the eyelids ; 
the bulbar, covering the sclerotic ; and the retro-tarsal folds, 
uniting these two, which form the sulcus or fornix, upper 
and lower. When the conjunctiva reaches the margin of 
the cornea it overlaps the latter slightly, and this over- 
lapping portion is known as the limbics conjunctivae, or 
cornese. At the inner angle or canthus, there is a vertical 
crescentic fold, the plica semilunaris, on the nasal side of 
which is a rounded mass of modified skin called the caruncle. 

The Examination of the Conjunctiva. — Simple in- 




Fig. 89.— First steps in evcrsion FIG. 90!— Everted lids held in 
of upper lid. position with one hand. 



Bpection in good diffused daylight, the patient facing the 
window, is better than nrtifical illumination. The whole 

127 



128 



DISEASES OF THE EYE. 



[chap. v. 



of the mucous membrane should be examined, and for this 
purpose the lids must be everted. The eversion of the lower 
lid is a simple matter, but a certain amount of practice is 
required in the case of the upper lid. 

Eversion of the upper lid. - The surgeon should face the 
patient and direct him to look down and to keep looking 
down, so as to render the upper edge of the tarsus accessible. 
The point of the thumb of one hand is then placed on the 




Fig. 91. — Method of examining a child's eye. 



outer surface of the lid, just above the tarsus, and with 
it the skin is drawn a little upwards and backwards ; this 
causes the margin of the lid to start forwards. The eyelashes 
(or the margin of the lid) are then taken between the thumb 
and forefinger of the other hand, Fig. 89, and raised upwards 
while the thumb above is depressed. The thumb which acts 
as the depressor should not be taken away too soon, a mistake 
often made by beginners, and it is better to slide it away 
sideways. In case of failure a probe or glass rod can be 



CHAP. V.] 



THE CONJUNCTIVA. 



129 



used iustead of the thumb. When everted, the lids can be 
retained in position by one hand (Fig. 90), while applications 
are being made to the conjunctiva. 

Th'> method of examining the. conjunctiva and cornea in 
infants and children is shown in fig. 91. The head is firmly 
held between the surgeon's knees. The conjunctiva is easily 
inspected, as the lids become everted on merely attempting 
to open the eye by pulling on the skin near the lid margins. 
In order to examine the cornea, the lids must not be- allowed 
to become everted, but must be separated with the points of 




Fig.— 92. — Method of exposing a child's eye. 

the fingers placed on the ciliary margins as shown in figl 92. 
The cornea at first rotates under the upper lid, but soon comes 
into view. Care must be taken to avoid injuring the cornea 
with the finger nails, or using too great pressure on the eye, 
which might rupture a corneal ulcer ; and the surgeon must be- 
ware lest retained secretion should spurt up into his own eyes. 

The normal conjunctival surface of the upper lid is smooth, 
yellowish pink in colour, and the conjunctiva is adherent to 
the tarsus. The small branches of the tarsal arches can be 
seen running in a vertical direction, and the meibomian 
glands appear as yellowish or grey lines at right angles 
to the ciliary margin of the lid. The student should note 

9 



DISEASES OF THE EYE. 



[chap. v. 



the appearance and thickness of the edge of the normal 
tarsus when everted. Figs. 93 and 94 illustrate the method 
of inspecting the retro-tarsal folds and fornix ; the double 
eversion is necessary in cases of suspected foreign bodies in 
the fornix. 

The blood-vessels of the conjunctiva consist of the posterior 
conjunctival vessels derived from the palpebral vessels, and the 
anterior conjunctival vessels which pass backwards from the 
anterior ciliary vessels. In general affections of the conjunc- 
tiva the former are chiefly involved. Engorgement of the vessels 
of the conjunctiva is known as conjunctival congestion, in order 




Fig. 93. — Examination of retro-tarsal Fig. 94. — Exposure of upper 
folds of upper lid. fornix ; lid everted and 

raised with retractor. 

to distinguish it from ciliary congestion, which accompanies 
diseases of the cornea and iris. It is bright red in colour, 
most marked towards the fornix, and is formed by a network 
of large, tortuous, superficial vessels, which move with the 
conjunctiva. Ciliary Congestion on the other hand is limited 
to the circumcorneal area, and diminishes towards the peri- 
phery. It is due to engorgement of the episcleral branches 
of the anterior ciliary vessels. It is pink or violet in colour, 
and is composed of minute straight radiating vessels, which 
are frecjuently indistinguishable to the naked eye as separate 
vessels. They are situated under the conjunctiva, and cannot 
be moved with it. In severe inflammations of the eyeball, 



CHAP. V.] 



THE CONJUNCTIVA. 



131 



such as a purulent ulcer of the cornea, the two forms of 
congestion are frequently present together. 

Hyperaemia of the Conjunctiva. — in this condition the 

blood-vessels of the palpebral conjunctiva are especially 
engaged. A slight serous exudation sometimes takes place, 
which may raise the conjunctiva around the cornea, a condi- 
tion know as chemosis (^aivco, to gape open). Small vesicles 
may form, and there may be some swelling of the papilla? 
and development of lymph follicles. Yet there is not 
any abnormal discharge from the conjunctiva, and herein 
lies the chief clinical difference between this affection and 
simple conjunctivitis. 

i 'arises. — Foreign bodies. Dust, foul air, or air loaded with 
tobacco-smoke. Alcoholic excesses. Accommodative asthe- 
nopia. Stenosis lacrimalis, and other forms of lacrimal 
obstruction. The use of unsuitable spectacles, or the use of 
the eyes for near work without spectacles, when the condi- 
tion of the accommodation (e.<?., hypermetropia, presbyopia) 
requires them. 

Symptoms. — The eyes are irritable. There is lacrimation 
and photophobia, with hot, burning sensations, and sensations 
as of a foreign body in the eye, and the eyelids feel heavy. 
All these symptoms are aggravated in artificial light. 

Tn fdment. — In addition to the removal of the cause, the 
instillation of a drop of tincture of opium and distilled 
water in equal parts morning and evening will be found 
beneficial. The eyes should be protected from the glare of 
light by dark glasses, and out-of-door exercise is to be 
recommended. 

Conjunctivitis in general. — The term Ophthalmia is 
commonly used as a synonym of Conjunctivitis, 1 which differs 

1 Wepharitis is sometimes called Ophthalmia tarsi, and to this there 
can be little or no objection, but the name Sympathetic Ophthalmia is 
liable to mislead, as this disease has nothing to do with the conjunc- 
tiva, but is an inflammation of the uveal tract. 



132 



DISEASES OF THE EYE. 



[chap. v. 



from mere hyperemia in the presence of abnormal secretion. 
Apart from mechanical or chemical irritation, inflammation 
of the conjunctiva is almost always caused by micro-organisms 
gaining access to the conjunctival sac ; or perhaps in some 
cases, by the sudden development, under favourable conditions 
of those which had been already present in a latent condition. 
They can easily be detected in the discharge, except in the 
rare cases of metastatic or endogenous origin, and are the 
cause of its infectious nature. Sporadic cases are very 
common, but the disease frequently spreads through the 
members of a household, or occurs as an epidemic. Infection 
takes place by the direct application of the secretion, or also 
— it is very generally thought — through the air, in which 
float particles of the infecting substance. This latter mode 
is especially liable to exist in an ill- ventilated room, where 
a number of people affected with conjunctival diseases are 
lodged with others who possess healthy eyes — e.g., in crowded 
charity-schools. It must be stated, however, that some 
authorities dispute the possibility of air-borne infection, upon 
the ground that most of the organisms which cause the various 
forms of infectious conjunctivitis are non-sporing, and are 
readily killed by drying. Inflammations of the conjunctiva 
are met with in patients of all ages, and at all seasons of 
the year ; but some forms are more common in the spring 
and autumn. The palpebral conjunctiva is often affected 
when the bulbar portion remains normal, and the conjunc- 
tiva of the lower lid is more frequently attacked than that 
of the upper lid. 

Differential Diagnosis. — The milder forms of conjunctivitis 
are apt to be mistaken, by those who are inexperienced, for 
iritis and vice versa, but with care there should be no diffi- 
culty in distinguishing between the two affections. Con- 
junctivitis is accompanied by conjunctival congestion, the 
secretion is muco-purulent,.and if not in sufficient quantity 
to be detected in the conjunctival sac. its presence is 



CHAP. V.] 



THE < 'OXJ UNCTIVA . 



133 



indicated by the fact that the lids are gniniiied together in 
the mornings. The pain is superficial and limited to the 
eve itself (sensation of foreign body, heat, itching). Vision 
is not affected, except temporarily by secretion on the surface 
of the cornea, which is easily removed by rubbing the lids 
over the eye. Iritis, on the other hand, is recognised by the 
presence of ciliary congestion, lacrimation instead of a sticky 
secretion, and by the character of the pain, which is neuralgic 
and circumorbital. Moreover, the vision becomes impaired 
at a very early stage of the disease. The ultimate diagnosis 
rests of course on the appearance of the iris and on the 
effect of atropine (see chap. xi.). 

Varieties of Conjunctivitis. — Although an accurate diag- 
nosis of the different forms of conjunctivitis depends on 
the discovery of the particular micro-organism in each 
case, nevertheless the usual classification, which is based 
on clinical appearances, must still be adhered to, partly 
because they are sufficient in most cases to indicate the 
line of treatment required, but chiefly because the type 
of inflammation excited by a given microbe is not sufficiently 
constant. In the majority of cases no doubt a definite 
group of symptoms is associated with a particular micro- 
organism, but occasionally the reaction takes a different 
form. 1 Again, one and the same clinical picture may be 
produced by different micro-organisms. In exceptional cases, 
too, a mixed infection may take place. 

From a clinical point of view then, conjunctivitis is 
divided into different varieties, depending on the nature 
of the discharge, the pathological changes in the tissues, 
and the severity of the symptoms. In Catarrhal Con- 
junctivitis, which may be acute or chronic, the discharge 



1 This may be due to altered conditions, such as differences in the 
resistance of the tissues or blood, or to variations in the degree of 
virulence of the microbe. 



134 DISEASES OF THE EYE. [CHAl>. v. 



is muco-purulent in character, whereas in Purulent Con- 
junctivitis pure pus is secreted. The discharge becomes 
fibrinous and coagulates to form a membrane, lying on the 
surface of the conjunctiva, or extending into the substance 
of the tissues in the Diphtheritic form. All inflammations of 
the conjunctiva are accompanied by more or less increase 
of the lymphoid tissue, which is of a diffuse character, but 
in certain cases lymphoid masses are formed which become 
visible to the naked eye, as in Follimdar and Granular 
Ophthalmia. In Phlyctenular Conjunctivitis small papules, 
or pseudo-vesicles, are found on the bulbar conjunctiva. 
Severe cases of conjunctivitis are often attended with slight 
swelling of the preauricular gland ; but in the condition 
known as Parina.ud's Conjunctivitis the glandular enlarge- 
ment is considerable, and reddish vegetations form on the 
palpebral conjunctiva. Traumatic Conjunctivitis may be 
produced by physical or chemical causes, and inflammation 
of the lacrimal sac frequently extends to the conjunctiva. 
In rare cases a Metastatic Conjunctivitis due to endogenous 
infection has been observed. Finally Eczema, Impetigo, 
and some of the exanthemata (Measles, Scarlatina, Small- 
Pox) are frequently accompanied by conjunctivitis. 

The Bacteriology of Conjunctivitis. — The micro- 
organisms which are commonly met with as the active 
causes of conjunctivitis are not very numerous. The 
following is a list of them, with the clinical type of disease 
to which each most frequently gives rise : — 

Bacilli. 

The Koch-Weeks B. — (Acute Contagious Conjunctivitis). 
The Diplobacillus (Morax)— (Subacute Angular C). The 
Diphtheria B. — (Membranous C). 

Cocci. 

The Gonococcus.— (Purulent C). The Pneumococcus.— 
(Catarrhal C). Streptococcus. Staphylococcus albus et 
aureus. 




IHplobacillus (Mora x and Axen- Koch-Weeks bacillus. Secretion 
/eld). From a case Of subacute from acute conjunctivitis. A few 



angular conjunctivitis. 



deeply stained Xerosis b. are also 
present. 




Pneumococcus. From a case of Gonococcus. From a case of 
catarrhal conjunctivitis. ophthalmia neonatorum. 




Xe-rori* bacillus. Culture from Xerosis bacillus. Culture, diph- 
normal conjunctiva, showing few theroid form, 
clubs. 

From preparations and drawings by L.W. 



CHAP. V.] 



THE CONJUNCT I VA . 



137 



The last two most frequently occur as part of a mixed 
infection, along with the gonococcus and the diphtheria 
bacillus. They are, however, also found, alone or together, 
in the conjunctivitis (often membranous) which accompanies 
impetigo of the face, or follows scarlatina, but they have 
never been known to cause an epidemic. 

The Xerosis Bacillus (see Xerosis), which is non-pathogenic, 
is very frequently present in the normal conjunctiva ; but 
it should also be remembered that some of the pathogenic 
forms, such as the staphylococcus, pneumococcus, and, it 
is stated by some, the streptococcus, are also found (especially 
the first named) in conjunctival sacs devoid of all signs 
of irritation. In fact the normal conjunctiva is rarely 
free from micro-organisms. 

All the above, with the exception of the gonococcus, the 
Weeks bacillus, and the diplobacillus, stain by Gram's 
method. 1 

The number of micro-organisms does not always corre- 
spond to the amount of discharge, and in some instances 
none can be found. We have recently had a case of this 
kind in which, although the discharge was profuse, both 
cover-glass preparations and attempts to obtain cultures 
gave negative results on three different occasions. The 
etiology of such cases is unknown. 

In addition to those which have been mentioned, other 
micro-organisms have occasionally been found. In the 
case of some of them it is very doubtful if they Avere 
tin- exciting cause of the condition with which they were 
associated. The most important varieties will be briefly 
referred to as we proceed. 

Catarrhal, or Simple Acute, or Muco-puruleut Con- 

1 Kor clinical work, in most cases, cover-glass smears stained by a 
basic aniline dye and by Gram's method will suffice, but in some cases 
the identity of the particular microbe can only be established by 
cultures and inoculation experiments, 



138 



DISEASES OF THE EYE. 



[chap. v. 



junctivitis. — In mild cases the affection is confined to the 
palpebral conjunctiva, often even to the conjunctiva of the 
lower lid ; but in the severer cases it extends to the bulbar 
conjunctiva. In the latter event the lids may be slightly 
hyperasinic and swollen. Both eyes are usually affected, 
either simultaneously, or at a short interval. Lymph follicles 
and enlarged papilla? are sometimes present. There is a 
sticky, thin, mucous, or mnco-purulent secretion, which 
causes the eyelids to be fastened together on awaking in 
the morning, and sometimes produces ulceration of the inter- 
marginal portion of the eyelids (intermarginal blepharitis). 
In some of the very mildest cases this ' stickiness ' or ' gum- 
ming ' on awaking in the morning is a valuable diagnostic- 
sign, for it is in such cases difficult or impossible to recognise 
by inspection the very slight variation from the healthy 
appearance of the conjunctiva. 

In the severer cases the papilla? are markedly swollen, and 
may even conceal the Meibomian glands from view. Also, 
one often sees small ecchymoses in the bulbar conjunctiva, 
especially in certain epidemics ; but these have no serious 
import. 

Minute grey infiltrations which may break down and 
form small ulcers, sometimes appear at the margin of 
the cornea, more especially in old jaeople. When there 
are many of them they may become confluent and form a 
small grey crescent, which ulcerates, and thus a crescentic 
marginal ulcer is formed, and very occasionally such an 
ulcer is followed by iritis. 

The catarrh may become chronic, and then the papilla? are 
more developed, while the blepharitis is liable to extend over 
to the cutis, causing eversion of the lower punctum lacrimalo 
with resulting lacrimation, and this, in its turn, aggravates 
the conjunctival affection. Indeed, chronic conjunctivitis is 
the commonest cause of ectropion of the lower lid in old 
people. The chronic form of the disease is much less 



CHAP. V.] 



THE COXJUNCriVA. 



139 



contagious than the acute, which frequently affects a whole 
family or may result in an epidemic. 

The Symptoms are those of a severe case of hyperemia 
(sensations of sand in the eye; hot, burning sensations; weight 
of the eyelid), with the addition of the annoyance consequent 
on the secretion, which, by coming across the cornea, may cause 
momentary clouding of sight. Photophobia is not generally 
severe unless there be some corneal complication. The 
symptoms are worse at night, or by artificial light, and 
are much less troublesome when the eyes are exposed to 
the air. 

Causes. — Anything which favours the entrance of micro- 
organisms into the conjunctival sac, such as direct infection 
with secretion, also dust, wind, etc. Conditions which lower 
the resistance of the tissues, either locally by causing 
hyperemia, or generally through the system (impure air, 
exposure to cold, etc.). Perhaps also the microbes are 
more widespread or more virulent at certain times, as in 
the spring or autumn. Some of the above-mentioned 
causes no doubt act in combination in the conjunctivitis 
which accompanies impetigo, scarlatina, measles, and small- 
pox. 

The Koch-Weeks bacillus produces an acute contagious 
conjunctivitis, which chiefly attacks young people, and 
occurs most frequently in an epidemic form. 

The type of inflammation resulting from the action of the 
/h'/dobacillus, on the other hand is of a subacute character, 
and is attended by a scanty secretion. It causes some 
redness or excoriation of the lower lids, most marked at 
the canthi ; hence the use of the name Angular Conjunctivitis. 
It is very prone to relapse. 

The Pneumococcus is responsible for a mild form of 
catarrhal ophthalmia, occurring generally in children, some- 
times in small epidemics. The secretion is at times 
fibrinous. This variety does not appear to be as common 



140 



DISEASES OF THE EYE. 



[chap. v. 



in the United Kingdom us elsewhere. It is of short 
duration (ten days or so), and can be readily cured. 

The conjunctivitis associated with impetigo sometimes 
assumes a mild catarrhal form. Both Strepto and Staphylo- 
cocci are found to he present. The former can no doubt 
set up conjunctivitis, but attempts to produce conjunctivitis 
in man with virulent cultures of staphylococcus aureus have 
proved ineffectual. 

In influenza epidemics conjunctivitis sometimes occurs 
along with the other symptoms, or it may precede them. 
It is due to the Influenza Bacillus, which is shorter and 
stouter than the Weeks B. but is difficult to distinguish 
from the latter. It is much rarer in adults than in 
children. 

Quite recently some cases of conjunctivitis have been 
observed, which were undoubtedly caused by the hay 
bacillus (B, Subtilis). In all of them particles of earth 
had found their way into the eye. 

The Prognosis is good, if there be no reason to suspect that 
the mild foi"m is but the commencement of a more severe 
inflammation. The infiltrations, and even the ulcers, which 
sometimes form at the margin of the cornea are not often 
of serious import, and usually heal, according as the treatment 
restores the conjunctiva to health. 

Treatment. — It will be advisable here to make a few 
observations on the treatment of conjunctivitis in general. 
Patients should always, in the first place, be warned of the 
danger of infecting others ; and in order also to avoid re-infect- 
ing themselves, droppers should be sterilized, or at least should 
not be brought into contact with the eye when used. For 
bathing the eye sponges shoidd be avoided, and small pieces 
of lint employed instead, which must be burnt immediately 
after use. Bandages should not be worn, nor should the 
patient be confined to the house, unless in severe or complicated 
cases. 



CHAP. V.] 



THE CONJUNCTIVA. 



141 



In catarrhal conjunctivitis cold or iced compresses, with 
the use of a 1 in 5000 solution of sublimate as a lotion, 
should be used frequently at the onset, and in mild 
cases will alone bring about a cure. But the habit, which 
some patients so readily acquire, of bathing the eyes fre- 
quently with cold water should not be permitted, for it is 
deleterious to the conjunctival affection. When in a clay or 
two the irritation and swelling have somewhat subsided — 
or from the very commencement, if there be not much 
irritation — a solution of nitrate of silver, of from 5 to 10 
grains to Jj, should be applied by the surgeon to the 
palpebral conjunctiva with cotton wool twisted on . the end 
of a small piece of stick, such as is used for matches, 
the lid being well everted. This then should be thoroughly 
neuti*alised with a saturated solution of common salt, the 
whole being finally washed off with plain water. The 
neutralisation with salt water is very important to check 
prolonged action of the nitrate of silver, as also to obviate 
conjunctival staining (called Argyrosis, from apyvpos, silver) 
when the treatment is a lengthened one. The application 
is to be repeated after twenty-four hours, by which time 
the slight loss of epithelium, the result of the superficial 
slough, will have been repaired. Immediately after such an 
application cold sponging or iced compresses are useful, 
and grateful to the patient. Gentle removal of the loose 
coagula also gives much relief. 

In recent years a number of organic salts of silver have 
been used instead of the nitrate. The best of these are pro- 
targol (20 per cent.) and argyrol (25 per cent.). They do 
not coagulate albumen, and are therefore supposed to have 
greater penetrating power, and are practically painless. 
In our experience the latter is the better of the two, 
but we would still rely on the nitrate in preference to 
either. 

Kvcn weak solutions of nitrate of silver as eye-drops to 



142 



DISEASES OF TIJE EYE. 



[CHAP. V. 



be used at home by the patient, should be avoided, for staining 
is very apt to be caused in this way. Protargol and argyrol 
have also been observed to cause it. 

Should the surgeon be unable to see the patient daily, 
astringent and antiseptic eye-drops are very beneficial, and 
indeed often effect a cure. Sulphate of zinc (gr. ij to the 
.).])> with or without Tinct. Opii, gj, alum (gr. iv to ^j), 
tannic acid (gr. v to viij to ^j) are those which are 
most commonly used. They may be combined with boracic 
acid in saturated solution, corrosive sublimate (1 — 5000), 
or oxycyanate of mercury (1 — 2000). Acetate of lead (1 
or gr. ij. to ^j) can also be pi-escribed, provided the cornea 
be intact ; otherwise deposits of lead are liable to form in 
it. Sulphate of zinc is a specific for diplobacillary con- 
junctivitis, but the treatment should be continued for 
some time after recovery, as the affection is very liable to 
relapse. 

A weak boracic acid ointment should be applied along 
the margins of the lids at bedtime. It prevents the adhesion 
of the lids in the morning, which is not only unpleasant to 
the patient, but also prevents free drainage of the secretion 
during the night. 

Acute Blennorrhcea of the Conjunctiva, or Purulent 
Ophthalmia. — -This very dangerous affection is most com- 
monly seen either as gonorrhoeal ophthalmia or as blennorrhrea 
neonatorum. 

Etiology. — In gonorrhoeal ophthalmia the etiological mo- 
ment is the introduction of some of the specific discharge from 
the urethra or vagina into the conjunctival sac ; while in 
blennorrhcea neonatorum the infection is believed to take 
place, either during or just after the passage of the head 
through the vagina, by abnormal secretion from the latter 
finding its way into the infant's eyes. A few instances have 
been observed of infants born with the disease. Prolonged 
labour, due to early rupture of the membranes, or faulty 



CHAP. V.] 



TEE CONJUNCTIVA. 



143 



head presentations, and also repeated examinations, would 
assist infection before delivery. Inoculation may also occur 
a few days after birth by pus conveyed by the fingers of the 
mother or nurse, or by towels, etc., used for washing the 
child's face. 

The more severe cases of blennorrhea neonatorum are 
caused by a vaginal discharge, which is almost always 
gonorrhoea!, and Neisser's gonococcus, which is the exciting 
agent, can be found in the discharge from the vagina and 
in the secretion from the eye. Mild catarrhal conjunctivitis 
also occurs in newborn infants, and in these cases the 
ordinary microbes associated with that condition are pre- 
sent ; 1 bat in rare cases even the gonococcus may produce 
a mild reaction, probably owing to attenuation of the virus 
by dilution or drying. It should also be noted that a 
typically purulent ophthalmia has, in exceptional cases, 
been observed in infants (Morax) without the presence 
of any micro-organisms, but it usually takes a benign 
course. 

If the infection take place during or immediately after 
birth, the disease appears from the second to the sixth day, 
according to the virulence of the secretion. If the inflam- 
mation come on later than the sixth day, it may be concluded 
that the infection was produced by the vaginal discharge 
being introduced into the eye by the fingers of the mother 
or nurse, etc. 

While purulent ophthalmia in adults is usually gonorrheal 
and due to the gonococcus, it may exceptionally be the 
result of infection by the Koch-Weeks bacillus ; the cases 
due to this bacillus, however, are not so serious as 
those caused by the gonococcus. In the rare cases of 
gonorrhoea! ophthalmia of metastatic origin, the gonococcus 



1 in some cases the bacterium coli lias been fouud, but that it actu- 
ally caused the conjunctivitis is doubtful. 



144 



DISEASES OF THE BTM 



[chap. V. 



cannot be found, as a rule, in the ocular secretion, and the 
inflammation takes on a mild character. True gonorrheal 
ophthalmia is sometimes met with in little girls. 

In newborn infants both eyes are commonly affected. 
The reverse is the case in adults, in whom also the disease 
is more severe. 

Symptoms and Progress. — In mild cases the bulbar conjunc- 
tiva may be but little, or not at all, affected, the palpebral 
conjunctiva alone becoming velvety and discharging a small 
amount of pus, while there may be no swelling or cedema of 
the eyelids. In severe cases of blennorrhea of the conjunc- 
tiva there is, soon after the onset, serous infiltration of the 
palpebral mucous membrane — which consequently becomes 
tense and shiny — serous chemosis of the bulbar conjunctiva, 
serous discharge, dusky redness, and swelling of the eyelids 
— which makes it difficult to evert them — pain in the eyelids, 
often of a shooting kind, burning sensations in the eye, 
and photophobia. This first stage, or period of infiltration, 
lasts from forty-eight hours to four or five days. The 
preauricular lymphatic glands may be swollen and tender, 
and a rise of temperature may occur. 

Then begins the second or purulent stage, in which, owing 
to swelling of the papilla?, the palpebral conjunctiva becomes 
less shiny and more velvety ; while the discharge alters from 
serous to the characteristic purulent form, the chemosis, how- 
ever, remaining unaltered, or becoming more firm and fleshy. 
The swelling of the lids continues, the upper lid often be- 
coming pendulous and hanging down over the under lid ; 
while, at the same time, it becomes less tense and more 
easily everted. Gradually the chemosis and swelling of the 
conjunctiva and eyelids subside, and the discharge lessens, 
the mucous membrane finally being left in a normal state, 
unless in a small percentage of cases in which chronic 
blennorrhea remains. A moderately severe attack of con- 
junctival blennorrhea lasts from four to six weeks. A 



CHAP. V.] 



THE CONJUNCTIVA. 



145 



delicate scarring of the conjunctiva in the fornices may be 
sometimes left after the attack. 

Complications with corneal affections f orm the great source 
of danger from this affection. They are found chiefly in four 
different forms. (1) Small epithelial losses of substance on 
any part of the cornea. If these occur at the height of the 
inflammation, they are apt to go on to form deep perforating 
purulent ulcers. (2) The whole cornea becomes opaque 
(diffusely infiltrated), and towards its centre some greyish 
spots form, which are interstitial abscesses or purulent in- 
filtrations. (3) The infiltration may form at the margin of 
the cornea, and extend a considerable distance around its 
circumference, giving rise to a marginal ring ulcer, and, 
later on, to sloughing of the whole cornea. (4) A clean- 
cut ulcer may form at the margin of the cornea without 
any purulent infiltration of the corneal tissue, and may 
also extend a long way round the cornea. Such ulcers are 
particularly apt to occur where there is much chemosis, 
which overlaps the margin of the cornea ; and, being hidden 
in this way, these iilcers are easily overlooked. The chemosis 
should be pushed aside with a probe, and these peculiar ulcers 
looked for. They are very liable to perforate. 

All the foregoing forms of corneal complication occur both 
in ophthalmia neonatorum and in gonorrhceal ophthalmia. 
They may appear at any period of the affection, but the 
earlier they occur the more likely are they to result seriously. 

The danger of these ulcers consists in the perforation of 
the cornea they are apt to produce, of which more later on. 

The severer the case, especially the more the bulbar con- 
junctiva is involved in the process, the more likely is it that 
cornea) complications will arise. For the corneal process is 
to be regarded as the result of infection by the conjunctival 
-'•'■retion ; and this infection is all the more apt to occur, 
where the nutrition of the cornea is impeded by a dense 
chernotic swelling of the bulbar conjunctiva. Severe chemosis 

10 



146 



DISEASES OF THE EYE, 



[chap. v. 



is less common in the blennorrhea of the new-born than in 
gonorrheal ophthalmia, and this may be the reason for the 
fact that the latter is much tbe more dangerous affection of 
the two. 

The Prophylaxis of purulent ophthalmia is a most im- 
portant matter. It should form part of the routine of 
lying-in practice. Careful disinfection of the vagina befoi-e 
and during birth, and the most minute care in cleansing the 
face and eyes of the infant immediately after birth with a 
non-irritating disinfectant (e.g., a solution of corrosive sub- 
limate 1 in 5000), are to be recommended. The method of 
the late Dr. Crede has found very general acceptance, and 
is an admirable one. It is as follows : — When, after division 
of the umbilical cord, the child is in the bath, the eyes 
are carefully washed with water from a separate vessel, the 
lids being scrupulously freed, by means of absorbent wool, 
of all blood, slime, or smeary substance ; and then, before 
the child is dressed, a few drops of a 2 per cent, solution 
of nitrate of silver are instilled into the eye. Many 
obstetricians employ this method now as a matter of routine 
in their lying-in hospitals for all the infants, whether or 
not it be suspected that there is danger of infection. 
The conjunctival irritation which sometimes follows this 
procedure is unimportant compared with the immense 
advantages which result from it. By its aid Crede reduced 
the percentage of his cases of ophthalmia neonatorum from 
8 or 9 per cent, to 0 - 5 per cent. 

In all cases of gonorrhoea it is the duty of the surgeon to 
explain to his patients what is the danger of their carrying 
any of the urethral discharge to their eyes ; and to charge 
them to exercise punctilious cleanliness as regards their 
hands and finger-nails, and care in the use of towels, hand- 
kerchiefs, etc. 

In respect of Local Treatment when the disease has become 
established :— In the very commencemenf of the affection 



CHAP. V.] 



THE CONJUNCTIVA 



147 



the only local applications admissible are antiseptic lotions 
(Permanganate of Potash Solution, 1 in 10,000 ; Sublimate, 
1 in 5000) and iced compresses, or Leiter's tubes. With 
the former the conjunctival sac should be freely washed 
or irrigated — not syringed — ont. In syringing ont the 
conjunctival sac a morsel of the corneal epithelium may 
be removed, and through this the cornea become infected, 
and thei'efore this method is objectionable. The iced 
compresses, or Leiter's tubes, should be kept to the eye 
for an hour at a time, with a pause of an hour, and so 
on, or even continuously. In this and in the next stage the 
chemosis should be freely, and daily, incised with scissors. 
If the swelling of the lids be great, the external canthus 
should be divided with a scalpel from without, leaving the 
conjunctiva uninjured, in order to reduce the tension of the 
eyelids on the globe, and, by bleeding from the small vessels, 
to deplete the conjunctiva. Depletion alone can be ob- 
tained by leeching at the external canthus, and in many 
cases is of great benefit at the very commencement. If 
in adults the chemosjs, palpebral swelling, and rapidity 
of the onset indicate that the inflammation is severe, 
it is well to place the patient quickly under the in- 
fluence of mercury by means of inunctions or small doses 
of calomel, as by so doing the chemosis is often rapidly 
brought down, and one source of danger to the cornea 
removed. 

In the second stage (i.e., when the conjunctiva has become 
velvety, and the discharge purulent) caustic applications are 
the most trustworthy, and in this respect iodoform and other 
lauded means cannot compete with them. The application 
employed may be a solution of nitrate of silver of 15 to 20 
grains in of water, which should be applied by the surgeon 
to the conjunctiva of the everted lids, and then neutralised 
with a solution of common salt ; or the solid mitigated 
nitrate of silver (one part nitrate of silver, two parts 



148 



DISEASES OF THE EYE. 



[chap. V. 



nitrate of potash) may be used, the first application being 
lightly made in order to test its effect, while careful 
neutralisation with salt water and subsequent washing with 
fresh water are most important. Iced compresses may be 
used to relieve pain. An interval of twenty-four hours 
should elapse before the application is renewed. No remedy 
is of greater value in purulent ophthalmia than mitigated 
lapis, when the proper indications for its use are present, 
and when it is applied with care and intelligence. Between 
the caustic applications, the pus should be frequently washed 
away from the eyelids, and from between the eyelids, with 
a 4 per cent, solution of boric acid, or with a 1 in 5000 
solution of corrosive sublimate, and boric acid ointment 
should be smeared along the palpebral margins, to prevent 
them from adhering, and thus retaining the pus. 

No corneal complication contra-indicates the active treat- 
ment of the conjunctiva by the method just described. Iodo- 
form, finely pulverised, has been much praised as a local 
application in the second stage of acute blennorrhea of the 
conjunctiva. It is to be dusted freely on the conjunctiva 
once or twice a day. For our part we should trust to it alone 
in mild cases only. It can, however, be employed with 
advantage in combination with the above treatment. 

Permanganate of potash in solution (1 in 5,000) is strongly 
recommended by some surgeons as a substitute for nitrate 
of silver, even in severe cases. They state that it can 
be used from the beginning, and with greater benefit. The 
conjunctival sac should be washed out with it three or four 
times a day. 

When but one eye is affected it is important to protect its 
fellow from infection by means of a hermetic bandage. This 
may be made by applying to the eye a piece of lint covered 
with boracic acid ointment, and over this a pad of borated 
cotton-wool. Across this, from forehead to cheek and from 
nose to temporal region, are laid strips of linl soaked in 



CHAP. V.] 



THE CONJUNCTIVA. 



149 



collodion in layers over each other ; or a piece of tissue 
guttapercha may take the place of the lint and collodion, its 
margins being fastened to the skin by collodion. The shields 
invented by Maurel and by Buller are serviceable for this 
purpose. Yet with careful instructions given to the patient, 
and average intelligence on his part, such protection of the 
sound eye is not necessary. In private cases we do not 
close the second eye, and have never had ill effects in 
consequence. Any sign of congestion was met by the 
application of a 2 per cent, solution of nitrate of silver, 
and it always proved sufficient to check the develop- 
ment of the disease, as it does in Crede's method of 
prophylaxis. 

Patients should be advised to sleep on the side of the 
affected eye, in order to prevent the discharge from trickling 
on to the other side of the face. 

Treatment of Corneal Complications. — The involvement of 
the cornea does not contra-indicate the use of the methods 
already described, but rather demands their vigorous applica- 
tion. In addition, atropine will relieve pain and diminish 
the tendency to iritis. Eserine is sometimes employed with 
the object of reducing the tension, and so improving the 
nutrition of the cornea by facilitating the lymph circulation, 
and also on account of its antiseptic properties. But, as 
its action on the normal tension is practically nil, and its 
antiseptic properties are very slight, it is better to reserve 
it for cases of marginal ulcer with prolapse, or danger of 
prolapse, of the iris, since by the contraction of the 
sphincter the iris is drawn away from the periphery. 
Greater care is now required in everting the lids, lest 
pressure on the globe should cause rupture of the ulcer ; 
and it must be remembered that when a case of acute 
blennorrhea first presents itself, the surgeon, not knowing 
the condition of the cornea, must use the utmost caution in 
making his examination, and yet must never fail to get a view 



150 



DISEASES OF THE EYE. 



[chap, v 



of the cornea for the purposes both of prognosis and of treat- 
ment. At each visit the cornea must be examined, and it may 
be found that, as the conjunctival process subsides, any exist- 
ing corneal affection also progresses towards cure, infiltrations 
becoming absorbed and ulcers filled up. But even though 
the conjunctiva be improving, and still more so if it be not, 
the corneal process may progress, the infiltration becoming an 
ulcer, and the ulcer becoming gradually deeper, until, finally 
it perforates. 

Should a corneal ulcer become deep, and seem to threaten 
to perforate, paracentesis of the floor of the ulcer must be 
resorted to without delay. By thus forestalling nature a 
short linear opening is substituted for the circular loss of 
substance, which would have resulted in the ordinary course 
of events. Through this small linear opening no prolapse 
of the iris, or else a relatively small one, takes place ; and 
consequently the ultimate state of the eye is usually a better 
one than it otherwise would have been. The reduction of the 
intraocular tension after the paracentesis promotes healing 
of the ulcer. It is often desirable to evacuate the aqueous 
humour, by opening the little incision in the floor of the 
ulcer with a blunt probe, on each of the two days after the 
operation. 

If an ulcer perforate spontaneously, the aqueous humour is 
evacuated, and, unless the ulcer be opposite the pupil and at 
the same time small in size, the iris must come to be applied 
to the loss of substance. Should the latter be very small, the 
iris will simply be stretched over it and pass but little into its 
lumen, and when healing takes place will be caught in the 
cicatrix, which is but slightly, or not at all, raised over the 
surface of the cornea, and the resulting condition is called 
Anterior Synechia. 

If the perforation be larger, a true prolapse of a portion of 
the iris into the lumen of the ulcer takes place. This prolapse 
may either act as a plug, filling up the loss of substance and 



CHAP. V.] 



THE CONJUNCTIVA. 



151 



keeping back the contents of the globe, but not protruding 
over the level of the cornea, or it may bulge out over the 
corneal surface as a black globular swelling, and may then 
play the part of a distensor of the opening, causing fresh 
intiltration of its margins. In either case cicatrisation will 
eventually occur ; and if the scar be fairly flat, it is called an 
Adherent Leucoma, but if it be bulged out, the term Partial 
Staphyloma of the Cornea is used. 

If the perforation be very large, involving the greater part 
of the cornea, with prolapse of the whole iris and closure of 
the pupil by exudation, the result is a Total Staphyloma of 
the Cornea. The lens may lie in this staphyloma, or it may 
retain its normal position, but become shrunken. 

The question of the treatment of a recent prolapse of the 
iris in cases of blennorrhoeic conjunctivitis is an important 
one. It has been, and is still largely, the practice to abscise 
small iris-protrusions down to the level of the cornea, or if 
large to cut a small bit ofl' their summits, with the object of 
obtaining flat cicatrices. Horner pointed out that in cases 
of blennorrhea this proceeding opens a way for purulent 
infection of the deep parts of the eye, and that serious conse- 
quences are not rare. He confined interference with the 
iris in these eyes to incision of the projapse, when it seems 
to be acting as a distensor of the opening, causing fresh 
infiltration of the cornea. Under other circumstances he 
restricted his treatment of the prolapse to the instillation of 
eserine, which has a marked effect in diminishing the size of 
the protrusion. 

A method of treating corneal ulcers of which we have 
no experience in purulent ophthalmia, but from which we 
have obtained good results in other cases, consists in 
covering the ulcer with conjunctival flaps. Goldzieher and 
Kuhnt speak favourably of the l-esults obtained by this 
method in purulent cases. The conjunctival sac should 
first be thoroughly washed out with a weak antiseptic or 



152 



DISEASES OF THE EYE. 



[CHAP. v. 



sterilized salt solution and any prolapse of the iris should 
be removed. (See also chap. vii.). 

It may occur that on the surgeon's visit to a case of 
blennorrhea of the conjunctiva, he will find the margins of the 
eyelids gummed together by sero-purulent secretion, while 
the eyelids are bulged out by the pent-up fluid behind them. 
The attempt to open the eye should then be very cautiously 
made, lest some of the retained pus spurt into the surgeon's 
eye. The surgeon should also be most careful to thoroughly 
wash and disinfect his hands and nails at the conclusion of 
his visit. 

In cases of blennorrhea neonatorum, when the ulcer has 
been small, on perforation taking place, the lens, or rather its 
anterior capsule, comes to be applied to the posterior aspect 
of the cornea. The pupillary area is soon filled with fibrinous 
secretion. The opening in the cornea ultimately becoming 
closed, the iris and lens are pushed back into their places by 
the aqueous humour which has again collected. Adherent to 
the anterior capsule on the spot which lay against the cornea 
is a morsel of fibrine, which gradually becomes absorbed by 
the aqueous humour. In the meantime changes have been 
produced by this exudation on the corresponding intra- 
capsular cells, which result in a small, permanent, central 
opacity at that place, where there is also a slight elevation 
of pyramidal shape over the level of the capsular surface. 
This condition is called central capsular cataract, or pyra- 
midal cataract, and rarely results from corneal perforation 
in adults. 

In cases of blennorrhea neonatorum an inflammatory 
swelling of the joints, so-called gonorrheal arthritis, is very 
occasionally seen. The gonococcus has been found in the 
fluid removed from the joints in some cases, while in others 
only the usual pyogenic cocci were present. Even more rarely 
do peri- and endo-carditis, pleuritis, and meningitis occur. 

* Membranous Conjunctivitis. — This disease is char- 



chap, v.] THE COXJUNCTIYA. 




acterised by the existence of a fibrinous exudation, either oH^^^sac*^ 
the surface or in the substance of the conjunctiva, in 
addition to the other symptoms of inflammation. It was 
formerly believed, on purely clinical grounds, that the mild 
form of the disease, known as croupous conjunctivitis, was 
totally different in nature from the severe or diphtheritic 
form, and later on this view seemed to be borne out by the 
discovery of the Klebs-Loeffler bacillus in the diphtheritic 
cases ; but further experience of the bacteriology of mem- 
branous conjunctivitis has altered this view. Not only is 
the diphtheria bacillus found in mild croupous cases, but 
any of the micro-organisms which commonly cause con- 
junctivitis, may give rise to fibrinous exudations and the 
formation of membranes. The same condition in varying 
degrees of severity can be produced by chemical irritants 
such as lime, ammonia, etc., and also by jequirity. Lastly, 
the diphtheria bacillus may, in rare cases, lead to a simple 
catarrhal inflammation without the production of a membrane. 
The presence of a membrane therefore is only a symptom 
and is not necessarily pathognomonic, although very suggestive 
of the Klebs-Loeffler bacillus as the cause. 

In severe cases strepto- and staphylo-cocci are generally 
asociated with the diphtheria bacillus, and indeed the 
streptococcus, staphylococcus, and pneumococcus acting alone 
can cause severe membranous inflammation with loss of the 
sight. 

There is reason to believe that the diphtheria bacillus 
can only act on the conjunctiva when the epithelium has 
been injured, say by a slight, even imperceptible trauma or a 
previous inflammation. 

Two micro-organisms which are closely related to the 
true diphtheria bacillus and which must be distinguished 
from it, are the non-pathogenic B. xerosis and the avirulent 
diphtheroid bacillus. .Since morphological and cultural 
differences are of doubtful value in separating the virulent 



151 



DISEASES Oh' 'I UK EYE 



[CHAP v. 



from the non-virulent forms, inoculation experiments are 
necessary to establish an accurate diagnosis. 

Microscopically the membrane consists of a fibrinous 
network containing leucocytes, a few epithelial cells and 
often micro-organisms. In the so-called croupous cases the 
underlying epithelium may or may not be adherent to it, 
but even in the latter event, although the epithelium 
separates along with the membrane, the surface left is 
smooth and becomes covered by regenerated epithelium, so 
that no trace of scarring occurs. 

On the other hand, in the severe or diphtheritic cases 
the submucous tissue is involved in the exudation, the 
vessels become compressed by it, and this leads to necrosis. 
When the dead tissue has been cast oft* a granulating surface 
is exposed which heals by cicatrisation. These are true 
granulations in the surgical sense, and are therefore quite 
different from the granulations of trachoma. 

Etioloyy. — Membranous conjunctivitis in all degrees of 
severity is mostly met with in children, more especially 
under four years of age. It often follows an attack of 
measles or scarlatina, and is frequently accompanied by 
eczema. 

One or both eyes may be attacked. It is an acute 
disease, which occurs sporadically or in epidemics, but 
a few chronic cases have been seen lasting for many 
months. 

Clinically, the mild or croupous form of the disease can 
readily be distinguished from the severe or diphtheritic; hence 
they will be described separately, with the understanding 
that the real nature of each case only be decided by careful 
bacteriological examination. 

Croupous Conjunctivitis. — The symptoms are those of 
catarrhal conjunctivitis, to which in a few days is added 
the appearance of a greyish pellicle on the palpebral con- 
junctiva, sometimes also on the retro-tarsal folds, but 



CHAP. V.J 



THE CONJUNCTIVA. 



155 



rarely on the bulbar conjunctiva. The false membrane can 
lie peeled off, leaving a mucous surface underneath which 
may or may not bleed. The lids, which may be red and 
swollen, are always soft and easily everted. After a week 
or so t he second or secreting stage sets in, with the appearance 
of a discharge, and the false membrane becomes separated, 
leaving a healthy mucous surface which gradually returns to 
its normal condition, without any trace of scarring. Observa- 
tions with reference to corneal complications vary in their 
results, some surgeons never having seen them while others 
have noted them in 40 per cent, of their cases. Constitutional 
symptoms are much less frequent than in the severe or 
diphtheritic variety of this affection. 

Treatment. — In the first stage iced compresses or Leiter's 
tubes applied to the lids, with antiseptic cleansing of the 
conjunctival sac. No caustic should be used in this stage, 
as it is apt to produce corneal changes. Sulphate of quinine 
sprinkled on the conjunctiva or in 2 per cent, solution is praised 
by some surgeons as a useful application at this period. In 
the secreting stage nitrate of silver applications should be 
made in the usual way. 

When the Klebs-Loe flier bacillus is the active agent 
antitoxin should be used. According to some, simple in- 
stillations into the conjunctival sac may suffice in these 
mild cases. (See Treatment of Diphtheritic Conjunctivitis.) 

Dijjhtheritic Conjunctivitis. — There is no more serious ocular 
disease than this, for it may destroy the eye in twenty- 
four hours ; while in severe cases treatment is almost power- 
less. Fortunately it is almost unknown in these countries. 

The subjective symptoms of its initial stage are similar, 
although severer, especially in the matter of pain, to those of 
hlennorrhreic conjunctivitis. The objective symptoms differ 
from those of blennorrhfjea, in that the lids are excessively stiff", 
owing to plastic infiltration of the sub-epithelial and deeper 
layers of the conjunctiva, while the surface of the mucous 



15fi 



DISEASES OF THE EYE 



[chap. v. 



membrane is smooth, and of a greyish or pale buff colour. If 
an attempt be made to peel off some of the superficial exuda- 
tion the surface underneath will be found of the same grey 
colour, not red and vascular, as in croupous conjunctivitis. 
This staye of infiltration lasts from six to ten days, and con- 
stitutes the period of greatest peril to the eye ; for while it 
lasts the nutrition of the cornea must suffer, and sloughing 
of that organ is extremely apt to take place. Towards the 
close of the first stage the fibrinous infiltration is eliminated 
from the eyelids, and the conjunctiva gradually assumes a 
red and succulent appearance, and at the same time a purulent 
discharge is established. This constitutes the second or blen- 
norrhoeic stage. A third stage is formed by cicatricial 
alterations in the mucous membrane, which often lead to 
symblepharon, or to xerophthalmos ; so that, even if the eye 
escape corneal dangers in the first and second stages, others 
almost as serious may await it in the final stage. 

Corneal complications are most likely to occur in the first 
stage, and are then also most likely to prove destructive to 
the eye. The earlier they appear the more dangerous are 
they. If the blennorrhoeic stage come on before corneal 
complications appear, or even before an ulcer contracted 
in the first stage has advanced far, they are more easily 
controlled. 

In the third stage corneal affections, if they occur, are of 
a chronic nature and generally accompanied by vascularisa- 
tion. 

This disease is nearly always combined with constitutional 
symptoms, such as fever, malnutrition, albuminuria, and is 
sometimes fatal, but strange to say, is very rarely followed 
by paralysis, even of accommodation. It has seldom been 
observed to follow diphtheria of the throat, although the 
opposite sequence is not uncommon. 

Treatment— -If due to the Klebs-Loetfler bacillus antitoxin 
serum is the sovereign remedy, and as the injections should 



CHAP. V.] 



THE CONJUNCTIVA. 



157 



be made as soon as possible, and the identification of the 
diphtheria bacillus takes time, any presumption of its 
presence should be acted upon without delay. Precautions 
should of course be taken to avoid the ti\msference of the 
disease to others. In cases caused by the pneumococcus 
Romer's pneumococcus serum 1 may be used. These remarks 
also apply to croupous conjunctivitis. 

Local treatment in the first stage should consist in cold 
or iced applications and antiseptics ; later on warm fomenta- 
tions, especially if the patient finds them more agreeable, 
can with advantage be substituted for the cold. In the 
secreting stage the same lines of treatment should be 
followed as in catarrhal conjunctivitis, except that greater 
precaution should be taken in using the nitrate of silver ; 
the greater the discharge the more freely it can be applied, 
and vice versa. Corneal ulcers must be dealt with, when- 
ever they arise, in the same way as though the case were 
one of blennorrhoeic conjunctivitis. When the purulent 
discharge ceases, solutions of soda, milk, or glycerine may be 
prescribed as lotions for the conjunctiva, to arrest, if pos- 
sible, the xerophthalmos. 

* Hay Fever. — This is not uncommon among the better 
classes in these countries, although it is rarely seen in our 
hospital out-patient departments. The symptoms, in those 
liable to it, appear in the early summer each year, and 
disappear again in the course of six weeks or two months. 
They consist in catarrh of the nostrils, accompanied by great 
itching of them and frequent sneezing ; while the conjunctiva, 
especially in the lower fornix, becomes somewhat hypersemic, 
and there is lacrimation. There is excessive itching of the 
eyes, which renders the patient most wretched, and forces 
him to rub his eyes violently. There is photophobia. The 
respiratory tract may become involved, with some bronchitis 



1 A rchir far Auijenhnlli, lii. p. 1. 



158 



DISEASES OF THE EYE. 



[chap. v. 



and asthma, and general malaise and elevation of tempera- 
ture are present. Sometimes the eyes alone are affected. 
There is no tendency to corneal complications. 

Treatment is of no avail in preventing the annual re- 
currence of the affection, nor is it of much use in alleviating 
the attack. No strong local application should be employed. 
Weak collyria, or ointments, of sulphate of zinc, or copper, 
boric acid, or sublimate, etc., may be tried. Cocaine or 
holacaine eye drops (2 per cent.) afford the best relief. Dark 
glasses should be worn. 

Dunbar's hay fever serum called pollantine, has been used 
with benefit in some cases. 1 

Trachoma (joa^i/?, rough), Granular Conjunctivitis, or 

Granular Ophthalmia (also called Egyptian Ophthalmia 
and Military Ophthalmia). — In this disease, in addition to the 
usual appearances of simple conjunctivitis, there are developed 
translucent greyish or pinkish-grey bodies about the size of 
the head of a pin or larger, situated in and close to the 
fornix conjunctiva?, chiefly of the upper lid. They also occur 
on the tarsus, in the lower fornix, and sometimes on the 
plica semilunaris, but are very rarely met with on the bulbar 
conjunctiva. The tarsal growths are smaller, natter, and 
yellower in colour than those seen in the fornix. These 
bodies are the trachoma bodies or granulations, or " sago " 
grains, they somewhat resemble the follicles of follicular 
conjunctivitis, except that they are paler, more irregular 
in size and less apt to occur in rows. 

Microscopically they exhibit the structure of lymphoid 
follicles, and consist of an outer zone of small lymphocytes 
and a central mass of larger endothelioid cells, amongst 
which some very large cells are found with irregular pro- 
cesses and cell-inclusions. These are the so-called " trachoma 
cells " or " corpuscle cells " ; they are supposed to be 



1 Devtsch. Med. Wochemclvrift, 1903, No. 9, p. 149. 



CHAP. V.] 



THE CONJUNCTIVA. 



159 



phagocytes or enlarged connective tissue cells, and have 
even erroneously been taken for protozoa, but since they 
exist in normal lymph follicles in other places, they are not 
in any sense specific. The cellular elements of the follicle 
lie in the meshes of a delicate reticulum, the follicle itself 
being surrounded by a vascular network and a more or less 
defined capsule. 

The unevenness of the conjunctival surface is still further 
increased by a luxuriant formation of papilla*, due to the 
folding of the inflamed and hypertrophied mucous membrane, 
which also leads to the development of microscopic glands and 
later on of small cysts. The latter are met with in the 
furrows between the papilla?, or they may be produced by solid 
downgrowths of epithelium, which become softened in the 
centre. The follicles ultimately become absorbed, or soften, 
and according to Raehlmann, extrude their contents on the 
surface. In any case their disappearance is followed by the 
development of fibrous cicatricial tissue, from the shrinking 
of which various complications, which shall be mentioned later 
on, ensue. The tarsus may be involved in the inflamma- 
tion, and in most cases a vascular, richly cellular layer 
(Pannus) forms in the cornea between the epithelium 
and Bowman's membrane. 

Etiology ami Cause. — There can be no doubt that this 
disease is contagious and that it is the result of a specific 
cause, of the nature of which we are at present ignorant. 
The numerous bacteriological examinations which have been 
made and even the recent ultramicroscopic investigations of 
K;u hlmann have led to no definite results. The histological 
changes are not peculiar to this disease alone — the papillary 
hypertrophy is well seen in chronic blenorrho;a, for in- 
stance — and even lymph follicles occur from other causes; 
for example, from atropine irritation and in tuberculosis. 
It may be that granular ophthalmia is something of the 
nature of the infective granulomata. 



160 



DISEASES OF THE EYE. 



[chap. v. 



Infection occurs only by transference of the secretion from 
one eye to the other by means of fingers, towels, handkerchiefs, 
etc. Hence the more slovenly in their personal habits, and 
the more crowded in their dwellings, families, schools, 
barracks, or nations may be, the more likely is this disease to 
spread from one individual to another when it once gains a 
foothold. A great deal, however, remains to be learned as 
to the manner in which contagion takes place. The in- 
fectiousness of chronic cases cannot be very great, for nurses 
and doctors rarely, if ever, become infected by their patients. 
Neither do we see trachoma patients infecting other patients 
in the hospitals in this country, where the disease is so 
prevalent. Were the infectiousness of the disease very great, 
even the precautions taken in a well-ordered hospital against 
contagion would hardly be .sufficient to prevent such an 
occurrence occasionally. 

Amongst the better classes, both here and elsewhere, the 
disease is very uncommon. High, dry, mountainous countries 
are almost free from it, so that, probably, the atmospheric 
conditions play some part in the etiology. 

Some hold that the affection is dependent on constitutional 
disease, such as scrofula, tuberculosis, syphilis, etc. ; but we 
cannot endorse this view. No doubt many of these patients 
are anaemic and out of health, but this is due to the moping 
habits they contract, and the little open-air exercise they 
take in consequence of their semi-blindness. 

The effect of race as a predisposing cause is doubtful. 
Jews are said to be peculiarly liable to the disease, but it 
must be remarked that in them as in others it only occurs 
amongst the very poor. 

Trachoma generally attacks both eyes and is an extremely 
chronic affection. An acute form is described, which, how- 
ever, must be very rare, as it is practically non-existent 
in Ireland, although the chronic variety of the disease is so 
common. 



criAP. v.] 



THE CONJUNCTIVA. 



101 



Acute Trachoma, or Acute Gramolar Ophthalmia. — The 
symptoms are those of a more or less acute purulent 
ophthalmia, associated with the characteristic appearances of 
trachoma. But it has been proved in many cases that the acute 
symptoms are really due to an additional infection by the 
gonococcus or Koch- Weeks bacillus, and therefore the diagnosis 
of acute trachoma cannot be depended upon without a care- 
ful bacteriological examination. 

Treatment. — In the early stage the treatment is the same 
as for acute blennorrhea, while at a later period the same 
methods are adopted as in chronic trachoma. 

Chronic Trachoma, or Chronic Granular Ophthalmia. — This 
disease is often unaccompanied by inflammation, and is then 
unattended by any distressing symptoms, except that the eye 
may be more easily irritated by exposure to cold winds, foreign 
bodies, etc., or more easily wearied by reading and other near 
work. At this period the conjunctiva will be found free from 
injection or swelling ; but greyish-white semi-transparent 
trachoma bodies, of the size of a rape-seed and less, will be 
seen disseminated over the conjunctival surface and protrud- 
ing from it. Gradually these trachoma bodies or granulations 
give rise to a more or less active vascular reaction, attended 
with swelling of the papillae and purulent discharge — in short, 
slight blennorrhea. This is the stage of progression (Fig. 95). 
The patients then begin to be more inconvenienced, owing to 
the discharge which obscures their vision, to sensations of 
weight in the lids and of foreign bodies in the eye, and to partial 
ptosis, which is often observable ; and this, consequently, is 
generally the earliest stage at which we see the disease. 
The enlarged papilla? often grow to a great size, completely 
hidiDg the granulations. In this stage the granulations 
may become absorbed, and the disease undergo cure ; but 
more commonly it makes further progress. Fresh granula- 
tions appear, while the old ones increase in size and 
undergo a peculiar gelatinous change. They then often 

11 



162 DISEASES OF THE EYE. [chap. v. 



become confluent, leaving only here and there an island of 
vascular mucous membrane. Sometimes the trachoma bodies 
are very small, and present the appearances of minute yellowish 
dots, and in this form they are not always easily found. 

Gradually the follicles become absorbed, or more rarely 
their contents are expelled, and the connective tissue pro- 
liferates so as to cause more or less extensive scarring of the 
conjunctiva. This constitutes the cicatricial stage of the 
disease. The scarring frequently presents a reticulated 
appearance, and in many cases assumes the form of a white 
line parallel to, and a few millimetres from, the free margin of 




Fig. 95 — Granular ophthalmia ; Fig. 96 — Granular ophthalmia ; 
progressive stage. cicatricial stage, with pannus and 

trichiasis. 

the lid, Fig. 96. The tarsus may undergo fatty degeneration 
or become hypertrophied, while the diseased conjunctiva on the 
inner surface of the lid causes entropion and distortion of 
the bulbs of the eyelashes, followed by irregular growth of 
the latter, with resulting trichiasis and distichiasis. These 
changes are represented in Fig. 97. 

The great danger of granular ophthalmia lies in the 
complications which may attend it or which follow in its 
wake ; the former consist in pannus, ulcers of the cornea, 
and severe purulent conjunctivitis, while the latter are the 
distortions of the lids and eyelashes just referred to. 



CHAP. V.] 



THE CONJUNCTIVA. 



163 



Pannus (Lat., a cloth rag) presents the appearance 
(Fig. 96) of a superficial vascularisation of the cornea, with 
more or less diffuse opacity, and often small infiltrations. It 
invariably commences in the upper portion of the cornea, 
extending generally over the upper half, and frequently 
remains confined to this region. But in many cases, at a 
later stage, it extends to the whole surface of the cornea ; 
this latter occurrence often takes place almost suddenly, 




Fig. 97 (Scemisch). 

a. Muscle ; b b, Tarsus having undergone fatty degeneration ; c, Atrophied 
Meibomian Gland ; d <?, Hypertrophied Papilla ; e, Cicatricial Tissue in the con- 
junctiva ; /, Tarsus. 



and the vascularisation and opacity sometimes become so 
intense as to present quite a fleshy appearance, completely 
hiding the corresponding part of the iris from view. 
Histologically pannus consists of a new growth, which is 
extremely rich in cells, and which closely resembles the 
conjunctiva when occupied with confluent granulations. It 
is in fact a vascular granulation tissue which grows in 
from the limbus and is situated between the corneal 
epithelium and Bowman's layer. After a length of time 
Bowman's layer becomes destroyed in places, and then 



164 



DISEASES OF THE EYE. 



[CHAP. v. 



the cellular infiltration gains access to the true cornea, 
and gives rise to permanent changes in its transparency 
and curvature. In some bad cases of old-standing pannus 
the latter undergoes a connective-tissue change. It then 
becomes smooth on the surface, and the vessels almost 
disappear, so that the cornea is covered with a thin layer 
of connective tissue, -which obstructs the passage of light 
and is not capable of cure. Small white deposits occur 
sometimes at the lower edge of the pannus near the centre of 
the cornea, they are superficial and can be easily scraped off. 

Another result of pannus, sometimes, is a bulging or 
staphylomatous condition of the cornea, the tissues of which 
have become so altered and weakened that they give way 
before the normal intraocular tension. 

A pannus in which as yet there is no connective tissue 
alteration, and where there is no staphylomatous bulging, 
is capable of undergoing cure without leaving any opacity 
behind, except that which may be due to ulcers that have 
been present. 

Pannus is usually a painless affection, but is sometimes 
accompanied by photophobia and ciliary neuralgia. It may 
come on at any stage of the disease, and causes defective 
vision, in proportion to the degree and extent of the opacity. 
Severe pannus is liable to induce iritis. 

The connection between pannus and the condition of the 
conjunctiva is not altogether evident. It was for long held 
that the corneal affection is due to mechanical irritation, caused 
by the rough palpebral conjunctiva ; but some are opposed 
to this view, and indeed severe pannus is often seen with a 
comparatively smooth conjunctiva, while with a truly rough 
conjunctiva the cornea is frequently perfectly clear. 1 There 
can now be little doubt that pannus is analogous to the 

' Harman (7'he Conjunctiva in Health and Disease: London, L906) 
points out that a conjunctiva which looks rough is sometimes soft to 
the touch, and vice versa. 



CHAP. V.] 



THE CONJUNCTl VA. 



165 



granular disease in the conjunctiva. It is, in fact, the same 
disease modified by reason of the different tissue in which 
it is situated, this different tissue being itself a modification 
of the conjunctiva ; and it would seem probable that the 
cornea becomes diseased by direct inoculation from the con- 
junctiva of the upper lid. Yet it is remarkable that the 
bulbar conjunctiva, lying between the upper margin of the 
cornea and the fornix of the upper lid, never becomes 
apparently diseased. 

Prognosis. — At any period prior to cicatrisation of the 
conjunctiva an attack of purulent blennorrhcea is liable to 
come on. If not too severe, this may result in a cure by 
absorption of the trachoma bodies, and should not be checked. 
If, however, the attack be very severe, the eye runs dangers 
similar to those of an ordinary attack of purulent con- 
junctivitis. These dangers are less the more complete and 
the more intense the pannus. 

On the whole, if the disease come under care at an early 
period, and if treatment be carried out strictly, vision will be 
retained in a majority of cases, although a radical cure may 
be difficult or impossible. These cases require to be under 
constant treatment for long periods, and the very lengthened 
time, and steady continuous treatment needed for a cure, are 
probably the main obstacles to that cure. In most cases 
of chronic granular ophthalmia, attendance three times a 
week for a year will be required, to effect anything that can 
be called a cure. The common experience is that patients 
attend for some weeks, and then, being very considerably 
relieved of their distressing symptoms, and finding their 
sight vastly improved, they cease attendance long before 
the disease has been eliminated, to return after a brief 
interval with a condition of things as bad, if not worse, 
than before. It is therefore desirable at the very outset 
of treatment to explain the tedious and dangerous nature of 
the ailment to each patient. 



1GG 



DISEASES OP TEE EYE. 



[chap. v. 



Treatment. — The aim of this is to bring about absorption 
of the trachoma bodies with the greatest possible despatch, in 
order to prevent the destruction of the mucous membrane 
to which they tend. No caustic application should be made 
with the object of directly destroying the trachoma bodies, for 
this can only be done at the expense of the mucous membrane 
around them. For chronic cases, with little swelling of the 
papillae (blennorrhea), and with little or no cicatrisation, 
the best application is the solid sulphate of copper lightly 
applied to the conjunctiva, especially at its fornix; but 
when there is considerable papillary swelling, a 2°/ solution 
of nitrate of silver, properly neutralised after its application 
with a solution of salt, or a light application of mitigated 
lapis, similarly neutralised, is to be preferred. Should there 
be ulcers on the cornea, or much inflammatory irritation of 
the eye, sulphate of copper should not be applied to the 
conjunctiva. An interval of twenty-four hours at least 
should be allowed to elapse between each application, whether 
of sulphate of copper or nitrate of silver, and cold sponging 
for fifteen minutes should be employed immediately after 
the application. A change of treatment will be occasionally 
required even if the remedy first used answer well in the 
beginning, and one or other of the following can be adopted. 
Pure liquefied carbolic acid has been used with good 
result, but we have no experience of it. It is applied with 
a camel's-hair pencil, and the excess washed off with plain 
water. Solution of Sublimate, 1 in 2000 to 1 in 1000, 
applied with lint or cotton-wool to the everted conjunctiva 
with some pressure and rubbing. Liq. plumb, acetatis dil., 
never to be used except with everted lids, and washed off 
with plain water by the surgeon ; and not even in this way 
if there be ulcers of the cornea, as the corneal tissue forming 
the floor of the ulcer is liable to become impregnated with 
a white deposit, probably the albuminate of lead, which is 
by no means easy to remove by operation subsequently. 



CHAP. V.] 



TEE CONJUNCTIVA. 



Tannin ointment : Tannin gr. j, to vaseline cjj, the size of 
half a pea, to be put into the eye once a day. Sulphate of 
copper ointment : same strength as the last, and to be used 
in the same way. Solution of alum : Gr. x to ^j of distilled 
water ; one drop in the eye once a day. Where an active 
pannus is present, atropine should be instilled into the eye 
once a day as a precaution against iritis. 

Some employ scarifications of the conjunctiva, when it is 
much swollen and the papilla? too exuberant; but we have never 
adopted them, fearing the resulting cicatrices. Brushing of 
the conjunctiva with a small stiff horsehair brush, or special 
metallic brush, is a form of scarification used by others, and is 




sometimes combined with applications of solution of sublimate ; 
and scraping of the conjunctiva with a sharp spoon, with 
subsequent rubbing in of corrosive sublimate solution, has 
been recommended. 

Again, it has been proposed to excise or abscise the 
trachoma bodies ; and this may perhaps be allowable if they 
are isolated and protrude much over the surface of the 
conjunctiva, but they can be more easily destroyed by a fine 
electro-cautery. 

Squeezing out the granulations between the thumb-nail, 
used to be practised by the late Sir William Wilde, of Dublin, 
and has recently again come into use. But the proceeding 
of ' expression ' is nowadays performed by means of an instru- 
ment instead of by the finger-nails. The best instrument 
for the purpose is Grady's trachoma forceps (Fig. 98). The 
retro-tarsal fold of the everted lower or upper lid is grasped as 



1«8 DISEASES OF THE EYE. [chap v. 



far back as possible by the instrument, compressed and drawn 
upon, and in this way the trachomatous tissue is squeezed out 
with little or no laceration of the conjunctiva. The instru- 
ment has to be re-inserted and a neighbouring part of the 
conjunctiva treated in the same way, and so on, until the whole 
conjunctiva of each affected eyelid has been operated on. 
The four eyelids may be manipulated at one sitting, and 
the evacuation should be so complete that a repetition of the 
proceeding will not be required. Particular care should be 
taken to i reach the part of the conjunctiva which is hidden 
under 1 the commissures. Some cases are immediately and 
permanently cured by this operation ; while others, although 
greatly benefited, will still require a further routine treatment 
with local remedies. Expression is indicated only where 
trachomatous substance can be pressed out. Our experience 
with this method leads us to regard it as a useful one 
for the acceleration of the cure of some cases of granular 
ophthalmia before the cicatricial stage has come on. 

Excision of the fornix conjunctivae has been proposed by 
Schneller, and largely practised by him and other surgeons. 
It is claimed for this method that it shortens the treatment 
of all forms of the disease ; that, after it, existing corneal 
processes undergo rapid cure ; that the granular disease in 
the palpebral conjunctiva, although not directly included in the 
operation, disappears quickly ; that recurrences of the disease 
are rarer than by other plans of treatment ; and that the 
resulting linear cicatrix has no serious consequence, and 
is as nothing when compared with the extensive cicatricial 
degeneration of the whole mucous membrane which the opera- 
tion is calculated to prevent. In order to avoid cicatricial 
contraction care should be taken during the operation, that 
sufficient mucous membrane be left to completely cover the 
globe when the patient looks down. Supplemental treat- 
ment with the customary local applications is employed until 
the cure is obtained. We find that this is a useful procedure 



Cll.U". V.] 



THE cny.JUNCTIVA. 



1C9 



in some cases. When the tarsus is much thickened Knhnt 
advises a partial or complete excision of it, including the 
conjunctiva over it, if the latter is diseased. 

Infusion of Jequirity (Abrus precatorius, Paternoster Bean), 
long used in the Brazils, was introduced to the notice of 
Emopean surgeons by de Wecker. The infusion is made by 
macerating 154 grains of the decorticised jequirity seeds in 16 
oz. of cold water (a 3 per cent, infusion) for twenty-four hours. 
Twice a day for three days the lids are everted, and the 
infusion thoroughly rubbed into the conjunctiva with a 
bit of lint. The result is a severe conjunctivitis of a some- 
what croupous tendency (even the cornea being often hidden by 
the false membrane), accompanied by great swelling of the eye- 
lids, much pain, and considerable constitutional disturbance, 
rapid pulse, and temperature of 100°, or more. At first the 
pannus becomes more visible, but as the inflammation sub- 
sides, it diminishes or even disappears, while complete cure 
of the granular ophthalmia itself is rarer. Iced compresses 
to the eyelids may be used during the inflammation. A 
fresh infusion (nob more than seven clays old) must be 
employed in order to secure the best reaction. The majority 
of surgeons, amongst them the authors, find the remedy 
harmless, if not always successful ; but a good many cases 
are on record where violent diphtheritic conjunctivitis, 
followed by blennorrhcea of the conjunctiva, and by more 
or less extensive ulceration of the cornea, and even com- 
plete loss of the eye, were produced. We have, occasionally, 
seen small superficial ulcers form on the cornea without 
further injury. De Wecker regards the presence of a 
purulent discharge from the conjunctiva as a contra-indica- 
tion for the remedy, which he finds is then liable to increase 
the intensity of the blennorrhea in a dangerous degree. 
Cases where there is little or no papillary swelling, but 
nearly dry trachoma with pannus, are the most suitable 
for its use, and we cannot recommend it too highly in these 



170 



DISEASES OF THE EYE. 



[chap. v. 



cases. It is marvellous to see the rapid and effective cures 
of the severest pannus by this remedy in properly selected 
cases. But the presence of well-marked pannus of the cornea 
without ulceration is the only thing that can render the 
employment of jequirity justifiable, and in addition to this 
the conjunctiva should be free from blennorrhea. 

The occurrence of acute dacryocystitis is said to form an 
unpleasant complication of the jequirity treatment, even in 
cases in which the sac was previously quite normal ; but we 
have never seen it to occur. 

Of late Jequiritol, 1 which is a sterilised preparation 
of Abrin, the active principle of jequirity, dissolved in 
glycerine, and standardized experimentally, has been used. 
As it is supplied in four different strengths its action can, 
to a certain extent, be controlled, and if the reaction 
be too great, Jequiritol-serum can be used to check it, 
either by simple instillation into the conjunctival sac, 
or by subcutaneous injection. Although it is safer than 
jequirity, nevertheless ulcers of the cornea and dacryocystitis 
have also been observed after its use. We, as well as 
others, find that strengths number I. and II. produce little 
or no effect. 

After the subsidence of the jequirity inflammation some 
of the local remedies, above referred to, should be regularly 
applied for the purpose of completing the cure of the 
conjunctival condition. 

Where pannus is present, an occasional drop of atropine 
should be instilled, in order to control the tendency to 
iritis. 

Besides local remedies, it is of great importance that the 



' P. KSmer Von Graft's Arohio f. OpJUlt. Hi. The jequiritol and 
serum can be obtained from E. Merck, Darmstadt. For hospital use 
it has the disadvantage oC being very much more expensive than 
jequirity. 



CHAP V.] 



THE CONJUXCTIVA. 



171 



hygienic surroundings of patients suffering from granular 
ophthalmia be seen to, and that they be obliged to spend 
a considerable time daily in the open air. 

If the upper lid be tightly pressed on the globe, as it 
sometimes is, the physiological pressure varying in different 
individuals, an impediment is offered to the cure by any 
method, and pannus is promoted. It is then necessary 
to relieve the pressure by a canthoplastic operation. (See 
chap, viii.) 

The operation of peritomy, which consists in the excision 
of a portion of the conjunctiva, about 5 mm. broad, around 
the corneal margin, or destruction of the vessels with the 
actual cautery, is sometimes useful in the treatment of 
pannus. 

It is too soon yet to gauge the value of treatment by 
X-rays, high-frequency currents, and radium, which have 
all been tried with varying results. 

Follicular Conjunctivitis. — This variety of conjunc- 
tivitis, is characterised by a catarrhal inflammation of a 
mild type, to which is added the presence in the conjunctiva 
of small round greyish- or yellowish-pink bodies the size 
of a pin's head, which disappear completely as the process 
passes off, leaving the mucous membrane as healthy as they 
found it. These little bodies are situated chiefly in the 
lower fornix of the conjunctiva, and may be discovered by 
eversion of the lower lid, when they will be seen arranged 
in rows parallel to the margin of the lid. Whether they 
are easily discovered or not depends on their size and number, 
and on the amount of co-existing hyperemia or chemosis of 
the conjunctiva. The structure of these bodies shows them 
to be lymph follicles. 

Follicular conjunctivitis usually attacks both eyes, and 
is a very tedious affection, lasting often for months. It 
is chiefly met with in children and most frequently in 
schools. Systematic examinations of the conjunctiva in 



172 



DISEASES OF THE EYE. 



[chai* v 



schools have shown that a very large number of the children 
have follicles in the lower fornix, and occasionally they 
may be seen in the upper lids towards the angles. Iu 
some cases post-nasal adenoids are associated with them. 
The conjunctiva is otherwise normal and the follicles produce 
no irritation or distress of any kind. To this condition 
the name " Folliculosis " is sometimes given, and it is 
believed that ib renders the eye more liable to catarrhal 
infection. When this occurs, follicular conjunctivitis is the 
result. 

The existence of lymph follicles in the normal conjunctiva 
is disputed, and it is of course possible that in cases in 
which they are found, their presence may be explained by 
the repeated but transient irritation, to which the con- 
junctiva, from its exposed position, is constantly liable. 

Considerable difference of opinion prevails as to the 
relation of this disease to trachoma, some believing that 
it is merely a mild or abortive form of the latter. The 
question cannot be definitely settled until we know the real 
nature and cause of these affections. Clinically they seem 
to be distinct, and from our observation in this country, 
where both are very common, there are no practical 
reasons for regarding them as different forms of the same 
disease. The chief points of difference are these: — Follicular 
conjunctivitis affects children, even in upper-class schools ; 
trachoma occurs at all ages, but mostly in adults, and is 
confined to the lower classes. In follicular conjunctivitis the 
follicles are, with rare exceptions, confined to the lower lid ; 
they are more uniform in size and more regular in their 
arrangement than in trachoma ; furthermore they never 
produce cicatrices, pannus, or any of the ill effects which 
follow trachoma. 

The Symptoms are much the same as those of catarrhal 
conjunctivitis. Frequently there is little or no injection of the 
bulbar conjunctiva, and the chief symptom is asthenopia — an 



CHAP. V.] 



THE CONJUNCTl VA. 



173 



inability to continue near work for any length of time — and 
much distress in artificial light. 

Causes. — These are much the same as in simple catarrhal 
conjunctivitis. The long-continued use either of atropine 
or of eserine is liable to bring on the disease. 

Treatment. — The most useful remedy in this troublesome 
affection is an ointment of sulphate of copper of from 
gr. ss. to gr. ij in gj of vaseline. The weaker ointments 
should be used at first, and later on the stronger ones if it 
be found that the eye can bear them. The size of half a 
pea of the ointment is inserted into the conjunctival sac with 
a camel's-hair pencil once a day. Eye-drops of equal parts of 
tincture of opium and distilled water are of use in some cases. 
Abundance of fresh air, with change from a damp climate 
or neighbourhood to a dry one, is of importance. If the use 
of a solution of atropine have induced the disease, it should 
be discontinued ; and if a mydiiatic be still required, a 
solution of extract of belladonna (gr. viij ad _^jj may be 
employed in its stead. 

In cases of pure folliculosis no local treatment is required. 
It may be well to add that no alarm should be created in a 
school on account of the occurrence of follicular conjuncti- 
vitis. The utmost that might be necessary would be the 
separation of those cases in which there was much discharge, 
which might spread the catarrhal inflammation. 

*Parinaud's Conjunctivitis. — This is a well-defined form 

of subacute conjunctivitis which attacks only one eye. It 
was first described by Parinaud in 1889. 1 The chief features 
of the disease are : The appearance of granulations or 
vegetations on the tarsal conjunctiva or fornices, with painful 
and considerable enlargement of the preauricular and neigh- 
bouring glands, on the same side as the affected eye ; the 
disease is ushered in with chills and malaise ; there is slight 
mucous, or fibrinous, secretion but no suppuration ; a complete 



1 Hociete (('Ophthalmologic de l'aris, 5 fuvrier. 



174 



DISEASES OF THE EYE. 



[CHAP. v. 



cure results in the course of some months, without any corneal 
complication or subsequent scarring. 

The upper lids become swollen and perhaps nodular to 
the touch ; there is sometimes chemosis, but the subjective 
symptoms are slight. The granulations are red or yellowish, 
at first semi-transparent, and vary in size, being at times 
only as large as the head of a pin, while at others they may 
even form polypoid growths. Small yellow granules and 
superficial erosions are also, often present, generally in the 
furrows between the large granulations. The glandular 
inflammation sets in along with, or immediately after the 
eye symptoms, and may end in suppuration. The sub- 
maxillary and sometimes even the cervical glands are affected. 
The last symptoms to disappear are ptosis and some amount 
of glandular enlargement. 

Cause. — Up to the present the cause is unknown, and no 
case of the communication of the disease to others has been 
observed. The theory of an animal origin, which was 
originally advanced, has not been proved. The histological 
changes according to Yerhoeff and Derby, 1 consist in areas 
of necrosis in the subconjunctival tissue and extensive in- 
filtration with lymphocytes and phagocytes, but no suppura- 
tion. The deeper layers are in a state of chronic inflammatory 
reaction. Hoor, 2 on the other band, found that the nodules 
exhibited a tubercular structure, but failed to obtain any 
evidence of their tubercular nature. The only affections 
with which this disease is liable to be confounded, are tra- 
choma and tuberculosis, from which it can be distinguished 
by its symptoms and course, as well as by bacteriological 
methods of examination. 

Treatment. — Simple antiseptic treatment is almost sufficient, 
but the duration of the disease may be shortened by excision 

1 Archives of OpMh. (1904), xxxiii., p. 389, and Klin. Monatsld., xliii. 
(1905), p. 705. 

2 Klin. Monatsbl., 1906, p. 289. 



CHAP. V.] 



THE C0NJVXCT1YA. 



175 



of large granulations, or galvanocautery, and incision of the 
glands if they suppurate. 

"Tubercular Disease of the Conjunctiva. — This disease 

usually commences in the palpebral conjunctiva of the upper 
lid or in the upper fornix, and very rarely on the bulbar 
conjunctiva, in the form of a caseating ulcer, or as an 
inflammatory new formation of the granuloma type, and is 
nearly always unilateral. The granular form occurs in the 
shape of small yellow or grey subconjunctival nodules, 
resembling miliary tubercles, or may result in the develop- 
ment of flattened outgrowths, cockscomb-like excrescences, 
or even pedunculated tumours. The margins of the ulcers 
are well defined, and their floors either of a yellowish 
lardaceous appearance, or covered with greyish-red granula- 
tions. The surrounding conjunctiva is swollen, and if the 
palpebral conjunctiva be much involved the lid becomes en- 
larged in every dimension, and the ulcerative process may 
soon destroy part of the lid. It may also extend to the bulbar 
conjunctiva, and the cornea may become covered with pannus. 
The preauricular and submaxillary glands usually become 
enlarged. The positive diagnosis of the nature of the disease 
can only be made by the discovery of the characteristic 
tubercle bacillus, which will distinguish this from secondary 
syphilitic ulceration of the conjunctiva, between which and 
the tubercular ulceration there is sometimes a resemblance. 
The appearance may sometimes be suggestive of trachoma, or 
even of a malignant growth. As it not infrequently happens 
that the bacilli elude detection owing to their scarcity, and 
that excised portions of the growths do not always show a 
typical tubercular structure, inoculation experiments may 
be necessary to remove all doubt. Tubercular conjunctival 
disease is usually unattended by pain, or there is only a 
slight burning sensation ; but, again, when the ulceration is 
extensive, severe pain may set in. 

The disease is very chronic, its progress sometimes ex- 



176 



DISEASES OP THE EYE. 



[chap. v. 



tending over many years. It is rarely met with except in 
youth. Some of those whose eyes are attacked are already 
the subjects of tuberculosis in other organs, but very 
many of them are perfectly healthy in that respect. In 
fact, we have reason to believe that tuberculosis of the 
conjunctiva is much more often a primary disease, the result 
of an ectogenic infection, even in cases where already 
tuberculosis exists elsewhere, than of infection occurring 
through the blood. Tubercle bacilli introduced into the 
normal conjunctival sac have, it is true, been found to be 
harmless, for the intact epithelium offers an insuperable 
obstacle to their entrance into the tissue. But a superficial 
loss of substance of the conjunctiva is sufficient to allow 
of its inoculation with the bacilli, and then the disease be- 
comes established. The frequent lodgment of foreign bodies 
under the upper lid explains why this is the most common 
place for the disease to begin. But although conjunctival 
tubercular disease is not often secondary to tubercular disease 
in other parts of the system, yet it is itself liable to be the 
starting-point of general tuberculosis. 

Treatment. — The fact last mentioned makes it most 
important, in cases of primary tubercular disease of the 
conjunctiva, to thoroughly eradicate the diseased focus so as 
to avert an infection of other organs, and this can often be 
effected. If the ulcers be not already too extensive they 
must be scraped, and the actual cautery freely applied to 
them. And they may be then dusted with iodoform. 
Injections of tuberculin are also useful (see chap. vii.). 
Where the disease has already spread to the cornea, 
sclerotic, iris, or chorioid, enucleation of the eyeball is 
imperatively called for. 

^Ophthalmia Nodosa. — This disease is caused by the 
irritation (chemical or mechanical) of the hairs of certain 
kinds of caterpillars. The hairs give rise to ' foreign 
body' granulomata, which appear as small nodules chiefly 



CHAP. V.] 



Till: CONJUNCTIVA. 



Ill 



on tbe lower part of the bulbar conjunctiva. Both clinically 
and microscopically the condition bears a resemblance to 
tuberculosis, hence it has also been called pseudo-tubercular 
conjunctivitis. The presence of the hairs makes the 
diagnosis positive. In nearly all cases there was a history 
of caterpillars having accidentally come into forcible contact 
with the eye. The nodules are small semitranslucent and 
reddish or yellowish grey in colour. The disease is chronic; 
as the elimination or absorption of the hairs takes some 
time, but it terminates in complete recovery, unless the 
hairs have made their way into the iris, in which case a 
severe iridocyclitis may be set up. 

*Lupus of the conjunctiva usually occurs as an extension 
of the disease from the surrounding skin, or rarely from the 
lacrimal sac, as in a case in the ' Mater ' Hospital, where the 
disease extended from the mucous membrane of the nose, 
through both lacrimal sacs, to the inferior palpebral conjunctiva. 
It is seen as a patch or patches of ulceration, covered with 
small dark-red protuberances or granulations, chiefly on the 
palpebral conjunctiva, which bleed easily on being touched. 

Like lupus of the skin, these ulcei-ations undergo spon- 
taneous healing and cicatrisation in one place (unlike tuber- 
cular ulceration in that respect), while they are still creeping 
over the surface in another direction. But we now know that 
lupus, wherever it occurs, is really a tubercular disease, and 
that the two forms differ only in their clinical aspect. 

The Treatment is scraping with a sharp spoon and the 
application of the actual cautery. Iodoform. Tuberculin. 
X rays. 

*Syphilitic Disease of the Conjunctiva occurs both as 

primary and as secondary disease. It will be treated of 
in chap, viii., on Diseases of the Eyelids. 

Ulcers of the Conjunctiva. — In addition to tubercular 
and syphilitic ulcers the following conditions may lead to 
ulceration of the conjunctiva : — Injuries, foreign bodies, the 

12 



17S 



DISEASES OF THE EYE. 



[chap. v. 



separation of sloughs or membranes, pemphigus, epithelioma, 
smallpox ; phlyctens also appear as small superficial ulcers 
on the bulbar conjunctiva at one stage of their existence. 

*Spring Catarrh, or Vernal Conjunctivitis.— The 
tarsal conjunctiva of the upper lid is invaded by hard 
flattened bodies of a pale pinkish colour arranged close 
together, and known as tesselated or pavement granulations 
(Fig. 99). They are slightly pedunculated. The conjunctiva 
assumes a milky-white opacity. The bulbar [ conjunctiva 




Fig. 99. — Spring catarrh. Upper lid everted. 
From sketch by L.W. 

becomes injected, slightly oedematous, and at the limbus 
somewhat elevated with hard, gelatinous-looking and nodular 
greyish swellings. The lower palpebral conjunctiva is often 
milky-looking, but never shows granulations. All these ap- 
pearances may be present in the same case, or any one 
(the bulbar appearances, or the pavement granulations, or 
the milky-white opacity) or two of them may be absent. The 
margin of the cornea itself is apt to be invaded (Fig. 100) 
with a more or less circular infiltration resembling arcus 
senilis. Very occasionally the cornea becomes seriously 



CHAP. V.] 



THE CONJUNCTIVA. 



179 



complicated by the growth on the limbus extending over a 
great portion, or even the entire cornea. There is some 
mucous or muco-purulent secretion, and the patient com- 
plains of the eyelids being stuck together in the morning, 
of difficulty of using the eyes for near work, of itching and 
burning sensations, and all these symptoms are increased 
by exposure to heat. The eyelids droop slightly, giving the 
patient a sleepy look. 

Strictly speaking the disease is not a catarrh. The condition 
of the upper lid might at first suggest granular ophthalmia. 




Fig. 100. — C'ircamcorneal growth in spring catarrh. 
Sketched by L. W. 

The pathological changes consist in hypertrophy of the 
subconjunctival tissue, especially of the elastic fibres, 1 and 
proliferation of the epithelium which sends solid or cystic 
processes into the stroma. It is still uncertain which of 
these is the primary change. The affection is chiefly met 
with in boys between six years of age and puberty, and 
is mostly bilateral. 

It makes its appearance with the advent of warm weather 
in the late spring or early summer, and generally dis- 
appears, or is much modified in the cool seasons, to return 
again with the next warm season, and this is liable to go 

1 Schick, 'Von Qrwfc'g Archivf. Opldh., xlviii. 1. 



180 



DISEASES OF THE EYE. 



[chap. v. 



on for a long series of years. In the intervals between 
the attacks the congestion and subjective symptoms disappear, 
but the other appearances persist until the recovery sets in. 
I The Treatment of the majority of these cases yields very 
unsatisfactory results. Protection glasses should be worn. 
So far as possible all exposure to great heat of sun or 
artificial heat should be avoided. If possible the patients 
should reside in a cool place in the summer. Weak astringent 
collyria, or ointments, may be used ; or iodoform ointment 
(1 in 15), a little put into the eye once a day ; or massage 
twice daily in conjunction with yellow oxide ointment. 
Dilute acetic acid 1 or 2m. to the ^j is also recommended. 
De Schweinitz recommends boroglyceride locally, and arsenic 
internally. Antipyrin and quinine internally have proved of 
use in some cases. For the tarsal granulations Theobald 
has found marked benefit from use of the roller forceps. 
Strong salicylic acid ointment (20 grs. — ^j) has been recom- 
mended, but it was tried in a couple of cases in the ' Mater ' 
without much effect. Adrenalin drops have proved very 
beneficial in some cases. 

'Conjunctival Complication of Smallpox. — Of this we 
have, fortunately, no experience. The following embodies 
.the views of the late Professor Horner, who studied the 
subject during an epidemic. A good deal of uncertainty 
prevailed previously, for the initial stages of the eye affection 
were not carefully observed by physicians, owing to the 
swelling of the eyelids, while the ophthalmologist saw only 
the results of the process in the period of convalescence. 

Smallpox pustules on the cornea are, Horner believed, 
extremely rare ; indeed, he saw but one such case. The most 
frequent and most serious mode of attack consists in a greyish- 
yellow infiltration in the conjunctiva close to the lower margin 
of the cornea, not extending to the fornix conjunctiva), nor 
far along the inner or outer margin of the cornea. It 
occurs in the eruptive stage, and is to be regarded clinically 



CHAP. V.] 



THE CONJUNCTIVA. 



181 



as a variola pustule. This infiltration or pustule gives rise 
to a corneal affection, as does a solitary marginal phlyctenula, 
either in the form of a marginal ulcer or as a deep purulent 
infiltration, ulcerating, perforating, leading to staphyloma, 
purulent irido-chorioiditis and panophthalmitis — results which 
are often first observed long after the primary conjunctival 
affection has disappeared. 

Horner believed that the germ of the conjunctival infiltra- 
tion makes its way between the eyelids, and that the constancy 
of the position of the infiltration below the cornea is accounted 
for by this theory, that part of the conjunctiva, with closed 
eyelids and eyeball consequently rotated upwards, being the 
most exposed to particles entering. 

Treatment. — On this ground he recommended the prophy- 
lactic use of boracic acid ointment on lint applied over the eye- 
lids. If a conjunctival pustule have already formed without 
any, or only commencing, corneal affection, he would destroy 
the pustule with fresh chlorine water, or with mitigated lapis 
carefully neutralised. Corneal complications are treated as in 
blennorrhcca of the conjunctiva or diphtheritis. 

The frequency with which the eyes become affected varies 
in different epidemics. 

As true post-variolous eye-affections, Horner recognised 
diffuse keratitis, iritis, and irido-cyclitis, with opacities in the 
vitreous humour, and glaucoma ; in the hemorrhagic form 
of the disease, haemorrhages in the conjunctiva and retina ; 
and, where pyaemic poisoning comes on, septic affections of the 
chorioid and of the retina take place. 

*Hyaline, Colloid, and Amyloid Degeneration.— This 

very rare disease is a primary affection of the conjunctiva 
and is not associated with amyloid disease in any other part 
of the system. It has been found combined with granular 
ophthalmia, but this was most likely due to a fortuitous 
coincidence of the two diseases. It is most frequently met 
with in patients between twenty and twenty-five years of 



182 



DISEASES OF THE ATA'. 



[chap. v. 



age, generally in one eye only, and is extremely chronic, 
lasting for years. The retro-tarsal folds and palpebral con- 
junctiva are chiefly attacked, but it may also involve the 
bulbar portion. It causes great tumefaction of the affected 
lid, without any inflammatory symptoms. The eyelid can be 
but partially elevated, and is often so stiff and hard that 
it can be everted only with difficulty. The conjunctiva is 
yellowish, wax like, non-vascular and friable. The disease 
ultimately extends to the tarsus. 

Microscopically, homogeneous masses are found in the 
conjunctiva, with variable staining properties, according to 




Fig 101. — Lymphoma of Fig. 102. — Same case 

conjunctiva. as fig. 101. 



which they are called Amyloid, Hyaline, or Colloid. 
Calcification occurs in the later stages. Kajhlmann believes 
that the amyloid changes are always preceded by lymphoid 
infiltration. Figs. 101 and 102 are from a case in the 
' Mater ' hospital which presented the clinical appearance 
of amyloid diseases with the histological structure of a 
purely lymphoid thickening. 

Treatment. — A partial removal of the diseased parts by 
the knife or scraping, is all that is necessary, as the re- 
mainder disappears spontaneously, and further excessive 
scarring is thus avoided. A very good result was obtained 
in the above case by this method. 



QltAP. V.] 



THE CONJUNCTIVA. 



183 



"Xerosis (|r>/po<?, dry), or Xerophthalmos, is a dry, 
lustreless condition of the conjunctiva, associated in the 
severer forms with shrinking of the membrane. There are 
two forms of the affection — the parenchymatous, which is 
a local affection, and the epithelial, associated with general 
malnutrition. 

In Parenchymatous Xerophthalmos there is a more or less 
extensive cicatricial degeneration of the conjunctiva, depen- 
dent upon changes in 
its deeper layers, while 
its surface and that of 
the cornea become dry, 
and the latter becomes 
opaque, and the eye 
consequently sightless. 
The conjunctiva shrinks 
so completely, in many 
of these cases, that both 
lids are found adherent 
in their whole extent 
to the eyeball, which is 
exposed merely at the 
palpebral fissure, where 
the opaque and lustre- 
less cornea is to be seen. 
From what remains of 
the conjunctiva, scales, 
composed of dry epithe- 
lium, fat, etc., peel away. The motions of the eyeball are 
restricted in proportion to the extent of the conjunctival 
degeneration. There is no cure for this condition. 

Fig. 103 represents a case of xerophthalmos, the result of 
pemphigus, which occurred in a patient at the Royal Victoria 
Eye and Ear Hospital. Here the eyelids were not wholly 
adherent to the eyeball, and the cornea remained clear. 




Fiu. 103. 



181 



DISEASES OF THE EYE. 



[chap. v. 



The Causes of parenchymatous xerosis of the conjunctiva 
are granular ophthalmia, diphtheritic ophthalmia, pemphigus, 
burns, and the condition is said to be very occasionally seen 
as a primary disease, described as essential sin-inking of the 
conjunctiva. Many observers altogether deny the existence 
of this primary disease, and maintain that the cases described 
as being of that nature are merely the result of pemphigus, 
and we are inclined to agree with this view. 

Treatment. — As cure is impossible in this form of xeroph- 
thalmos, the only indication is to afford relief, so far as it can 
be done, from the distressing sensations of dryness of the 
eyes which are complained of. The best applications are 
milk, glycerine, olive oil, and weak alkaline solutions, and 
the eyes should be protected from all irritating influences 
by protection goggles. Transplantation of mucous membrane, 
or temporary union of the lids as a rule only produce a 
transient improvement. 

Epithelial Xerosis of the coujunetiva is confined to the 
epithelium of that part of the conjunctiva which covers the 
exposed portion of the sclerotic in the palpebral opening. It 
there becomes dry and dull and covered with a white foam 
due to altered Meibomian secretion. The xerotic patches, 
whicb are triangular in shape, with the base at the corneal 
margin, are known as Bitot's Spots. The whole bulbar con- 
junctiva is loose, and easily thrown into folds by motions of 
the eyeball, and there may be a good deal of secretion. This 
form of xerophthalmos often occurs in epidemics, but also 
sporadically, accompanied by night-blindness (the light-sense 
unimpaired) and contraction of the field of vision. The 
combined condition has been noticed chiefly in persons of 
debilitated constitution, who have been exposed to strong 
glares of light, and is said to have appeared in epidemics, 
under these conditions, in foreign prisons and barracks. 
Epidemics have been chiefly seen in Russia, especially during 
the Lenten fasts. 



CHAP. V.] 



THE CONJUNCTIVA. 



185 



The dryness of the conjunctiva is due to cornification of 
the epithelium, which the tears cannot properly moisten. 
Xerosis bacilli are found in large numbers, but are not the 
cause of the disease. 

Treatment by rest, protection from glare of light, nutritious 
diet, and tonics, especially cod liver oil, invariably restore the 
eyes to their normal functions. 

Again, epithelial xerosis occurs in very young cachectic 
children, in connection with a destructive ulceration of the 
cornea (see Keratomalacia, chap. vii.). 

*PemphigUS of the Conjunctiva. — This is another rare 
disease. It has been seen in connection with pemphigus 
vulgaris of other parts of the body, but it also occurs as an 
independent disease. It is attended by attacks of much pain, 
photophobia, and lacrimation ; and the conjunctiva, at each 
place where subconjunctival exudation of serum has been 
situated, undergoes degeneration and cicatricial contraction. 
Such attacks succeed each other at shorter or loager inter- 
vals, for weeks, months, or years, until, finally, the entire 
conjunctiva of each eye may have become destroyed, and the 
eyelids are adherent to the eyeball. The cornea gradually 
becomes completely opaque, or, having ulcerated, becomes 
staphylomatous. In the course of the disease the eyelashes 
are apt to become turned in on the eyeball, or even entropion 
may form ; and these conditions aggravate the suffering of 
the patient. 

The foregoing is a description of a severe case. In less 
severe cases the conjunctiva may not be completely destroyed, 
and the cornea may not be affected. 

Bulhe are seldom seen, for the conjunctival epithelium is 
so delicate that the serous exudation beneath it breaks it 
down at once. Consequently, the conjunctival surface is 
found in these cases to be covered by what looks like a 
membranous deposit, upon removal of which a raw surface 
is exposed ; and these appearances have led to the mistaken 



186 



DISEASES OF THE EYE. 



[chap, v 



diagnoses of croupous and of diphtheritic conjunctivitis. 
Rarely deep-seated bluish cysts are present. They existed 
in the case illustrated by Fig. 103. 

Treatment is helpless in respect of arresting the progress of 
the disease, or of restoring sight when lost in consequence of 
it. The most one can do is to relieve the distressing symptoms 
by emollients to the conjunctiva, and by the use of closely 
fitting goggles, to protect from wind, dust, and sun. Inter- 
nally, arsenic is indicated. 

Pinguecula (pinguis, fat) is the name given to a small 
yellowish elevation on the exposed part of the bulbar con- 
junctiva near the margin of the cornea, usually at its inner 
side, more rarely at its temporal margin, but sometimes in 
each place. It is most commonly seen in old people as 
a triangular patch or rounded tumour. Notwithstanding 
its name, it contains no fat, but is composed of connective 
tissue, hyaline deposits, and elastic fibres. It is supposed 
to be due to the irritation caused by small foreign bodies. 
It rarely grows to a large size, and requires no treatment 
unless it become very disfiguring, when it may be removed 
with forceps and scissors. When an eye becomes congested 
or ecchymosed, the pinguecula, if present, stands out as 
a white or yellow patch and may lead in some cases to 
mistakes in diagnosis. 

Pterygium (irrepv^, a wing). — This is a vascularised 
thickening of the conjunctiva, triangular in shape, situated 
most usiially to the inside of the cornea, sometimes to its 
outer side, but never above or below it. The upper and 
lower margins of the triangle are limited by a shallow 
depression or fold. The blunt apex of the triangle, or 
head of the pterygium, is on the cornea ; and its base, 
the body, at the semi-lunar fold. The neck of the 
pterygium is that part of it at the margin of the 
cornea. There is frequently, but not always, a tendency of 
the growth to advance into the cornea, of which it seldom 



CHAP. V.] 



THE CONJUNCTIVA. 



187 



reaches the centre, and still more rarely extends quite 
across it. 

In its early growth the pterygium is somewhat thick and 
succulent-looking, and very vascular ; but finally it ceases 
to grow, and then becomes thin and pale, and this is its 
retrogressive stage ; yet it never entirely disappears. Sight 
is not affected unless the pterygium extends over the pupillary 
region of the cornea. A limitation of the motion of the eye 
to the other side, and consequent diplopia, is sometimes caused 
by a pterygium ; but, for the most part, the disfigurement 
alone it is which brings these cases to the surgeon. 

Cause. — It was formerly believed that the starting-point 
of a pterygium was an ulcer at the margin of the cornea, 
which in healing caught a morsel of the limbus conjunctivae 
and drew it towards the cicatrix, throwing the mucous 
membrane into a triangular fold. But ulcers are never 
found at the apex of a true pterygium, and the condition 
brought about in this manner is known as pseudopterygium 
and differs in many ways from true pterygium. The false 
pterygium may occur at any part of the circumference of 
the cornea. It is very variable in shape, is non-progressive, 
and in most cases a fine probe can be passed under the 
neck of the growth where it bridges over the limbus. 
Again in a false pterygium a nebula or leucoma is frequently 
found at the apex. 

Fuchs believes that pterygium develops from the Pin- 
guecula, and that the latter causes nutritive changes in the 
cornea, loosening the superficial lamellse, and allowing the 
connective tissue of the limbus to grow in on the cornea. 

Pterygium is a rare affection in this country, but is more 
common in countries or localities where the air is filled with 
fine sand or other minute particles. 

Treatment. — Unless the pterygium be very thick, and have 
invaded the cornea to some extent, or be progressing over the 
cornea, it is well to let it alone ; the more so as by removing 



188 



DISEASES OF THE EYE. 



[chap. v. 



it a quite normal appearance is not given to the eye, for a 
mark is necessarily left both on cornea and conjunctiva. If 
it be progressive or very disfiguring, it should be removed, 
other proposed modes of dealing with it being futile. This 
may be effected either by ligature or excision. 

In the method by ligature a strong silk suture is passed 
through two needles. The pterygium being raised with a 
forceps close to the cornea, one needle is passed under it here 
and the other needle in the same way close to its base, the 
ligature being drawn half-way through. The thread is cut 
close behind each needle, thus forming three ligatures, which 
are respectively tied tight. In four or five days the pterygium 
comes away. 

For excision the apex is seized with a forceps and dis- 
sected off either with a scissors or fine scalpel, care being 
taken not to injure the true cornea ; or a good plan is to pass 
a strabismus hook under the pterygium when raised up from 
the sclerotic, and to forcibly separate the corneal portion by 
drawing the hook under it. The dissection is continued 
towards the base of the pterygium, where it is finished with 
two convergent incisions meeting at the base. The mucous 
membrane in the neighbourhood of the base is separated up 
somewhat from the sclerotic, and the margins of the con- 
junctival wound are then carefully brought together with 
sutures. Skin grafts, according to Thiersch's method, have 
been used with success to cover the defect. 

*Lithiasis consists in the calcification of the secretion of the 
Meibomian glands, which are seen as small white or yellowish 
spots not larger than a pin's head in the conjunctiva. There 
may be one only or very many. Concretions similar to 
these but more superficial also occur in the lower fornix ; 
they are found in the interior of newly formed glands which 
have become cystic. These concretions often give rise to 
much conjunctival irritation, and if they protrude over the 
surface of the conjunctiva may injure the cornea. Each 



chap, v.] THE CONJUNCTIVA. 189 



one — the eye having been cocainised — must be separately 
removed by a needle, with which first an incision has been 
made into the conjunctiva over the concretion. 

Uric acid dejwsits have been observed in the palpebral 
conjunctiva in gouty patients. 

•Conjunctivitis Petrificans. — Under this title Leber has 
described a rare and remarkable disease of the conjunctiva. 
In the course of a brief period, and accompanied by some 
slight inflammatory reaction, a stony hard, white, chalky 
substance is deposited, in more or less extensive patches, 
in the previously healthy conjunctiva, the deposit being 
scarcely raised over the conjunctival surface. The disease 
attacks a part of the bulbar or palpebral conjunctiva, and 
may extend to the intermarginal portion of the eyelid. 
One or both eyes may be attacked. After a time, which 
varies from a week to several months, the deposit is thrown 
off or absorbed, and the affected part suffers either no 
detriment or there may be slight thickening and shrinking. 
There is no great tendency to corneal complications, but 
slight marginal ulcerations, which heal readily, occasionally 
occur. In one case severe diffuse opacity of the cornea 
seriously affected the sight. Frequent relapses are liable 
to take place in the same or in different parts of the con- 
junctiva, and the whole course of the affection may extend 
over several years, and then end in complete cure. 

No cause has as yet been assigned for this disease, 
although Leber suspects it to be an ectogenic microbic 
infection. The only treatment which seems to be of use 
is warm fomentations, and the careful operative removal 
from time to time of the chalky scales as they become 
loosened from the main mass. 

Subconjunctival Ecchymosis. — The rupture of a small 
subconjunctival vessel in the bulbar conjunctiva, without 
conjunctivitis, is of frequent occurrence. It suddenly gives a 
more or less extensive purple hue to the ' white of the eye,' 



190 



DISEASES OF THE EYE. 



[chap. v. 



causing the patient much concern. It is common enough in 
old people, but may occur in the young, and even in children, 
from severe straining, as in hooping-cough, vomiting, or raising 
heavy weights. It is occasionally significant of diabetes. It 
also occurs sometimes during epileptic fits, and profuse sub- 
conjunctival haemorrhage is occasionally found in cases of 
fracture of the base of the skull, having made its way along 
the floor of the orbit. It is of no importance so far as the 
integrity of the eye is concerned. 

Treatment. — The extravasated blood becomes absorbed 
without treatment, but dionine may accelerate the process. 

Subconjunctival Serous Effusion. Chemosis.— This 

has been previously alluded to in connection with some 
forms of conjunctivitis, but it may appear in inflammatory 
affections of the neighbouring parts (orbit, lacrimal sac, 
eyelids). A stye for instance is sometimes accompanied 
by well-marked chemosis. Dionine also produces a serous 
exudation which is preceded, however, by an initial stage 
of congestion. In Bright's disease a slight degree of 
chemosis often occurs. 

Treatment. — As a rule no special treatment is required 
beyond that of the disease of which it forms a symptom, 
but if it be excessive the conjunctiva may be snipped with 
a scissors, with very good effect. 

Injuries Of the Conjunctiva. —Foreign bodies frequently 
make their way into the conjunctival sac, and cause much 
pain, especially if they get under the upper lid, by reason, 
chiefly, of their coming in contact with the corneal surface 
during motions of the lid and of the eye. If the foreign body 
be under the lower lid it will be easily found on drawing 
down the latter, and, provided it be not actually embedded 
in the mucous membrane, which is a rare occurrence in 
the lower lid, it is easily removed with a camel's-hair 
pencil or with the corner of a soft pocket-handkerchief ; but 
if the foreign body be under the upper lid it is necessary to 



CHAP V.] 



THE CONJUNCTIVA. 



191 



evert the latter before it is reached. Should tho foreign 
body be embedded in the conjunctiva it must be pricked out 
of its position with the point of a needle or other suitable 
instrument. 

Large foreign bodies, such as a grain of wheat, may lie 
hidden in the upper fornix for several weeks. We have 
seen ulceration of the cornea caused in this way, and 
also cockscomb-like granulations in the fornix. 

The conjunctiva is frequently injured in severe wounds of 
the eyelids or eyeball. The interest and treatment are centred 
here chiefly on the other more important parts, which have 
been injured. A tear or wound of the conjunctiva (ustially 
of the bulbar portion), when it occasionally occurs without 
injury to other parts, is in general of very slight moment. 
If the wound be expensive its edges should be drawn together 
with a few points of suture ; but otherwise healing will 
take place with the aid simply of a bandage to keep the 
eye closed for a few days. 

A common form of injury, which may involve the con- 
junctiva alone, is a burn by acid or lime. In the case of a 
strong acid getting into the eye, if the patient be seen imme- 
diately after the occurrence, the whole conjunctival sac should 
be well washed out with an alkaline solution (1 per cent, soda 
solution). In the case of lime, after all the larger particles 
have been most carefully removed from the eye with forceps, 
a weak solution of a mineral acid may be used for washing 
out the conjunctival sac ; or, as is recommended by some, 
a solution of sugar as thick as syrup may be poured into 
the eye. Later, olive or castor oil, or even butter, may be 
applied, the subsequent treatment being continued with 
weak sublimate ointment. Cocaine may be employed to 
relieve the pain. But even in the case of unslaked lime 
the conjunctiva may be washed with plain water, provided 
plenty be used and that the operation be done quickly. 
The heat generated by the slaking of the lime is developed 



192 



DISEASES OF THE EYE. 



[chap. v. 



slowly, and further it is the chemical action rather than 
the heat which is injurious. 

In the case of a severe burn of the conjunctiva, the resulting 
cicatrix is liable to produce a more or less extensive union of 
the eyelid to the eyeball (Symblepharon), which often interferes 
with the motion of the latter, or even with vision, if the 
cornea be obscured. No measures taken during the healing 
process can prevent symblepharon if the degree of the burn 
be such as to bring it about. The relief of symblepharon by 
operation will be dealt with in chap, viii., on Diseases of the 
Eyelids. 

Cysts. 

"Simple Cysts of the conjunctiva are very rare. They 
appear as clear spherical protuberances of about the size of 
a pea, seated usually on the bulbar conjunctiva. The walls 
of the cysts contain but few vessels, are thin, and almost 
transparent; while for contents they have a clear limpid fluid. 
These cysts cannot as a rule be moved from their position, 
because they are adherent to the conjunctiva, which indeed 
takes part in the formation of their walls. The majority 
are dilated lymphatic vessels, as shown by their endothelial 
lining. Small beadlike strings of dilated lymphatics are very 
frequently seen on the bulbar conjunctiva. Retention cysts 
are also developed in Henle's and Krause's glands, as well 
as in the so-called glands resulting from chronic inflammatory 
conditions. Implantation cysts, due to proliferation of in- 
cluded surface epithelium, occur ns the result of injury, 
and congenital cysts are also met with. 

Treatment. — The cysb may be dissected out, or it may be 
sufficient to abscise its anterior wall, and scrape or cauterise 
the interior. 

*Subconjunctival CysticerCUS is a little more common 
than simple cyst of the conjunctiva, and yet only about 
fifty-five examples of it have been recorded, 



CHAP. V.] 



THE COXJUXCTIVA. 



193 



Cysticercus is distinguished from simple cyst by its free 
mobility under the conjunctiva, to which it is not attached ; 
by its thicker and more vascular walls ; and, above all, by 
the presence of a round, white, opaque spot on the anterior 
surface, first pointed out by Sichel, and looked on by him 
as pathognomonic of a cysticercus. This spot indicates the 
position of the receptaculum ; and occasionally, when this 
comes to be placed on the posterior surface of the cyst, it 
may be difficult, or impossible, to make the diagnosis with 
certainty, but in doubtful cases the character of the hooklets 
and the tuberculated cyst-wall will solve the question after 
excision. 

Treatment. — The cyst may be pushed to one side under the 
conjunctiva, an incision made in the latter, the cyst then 
pushed back again, and dissected out through the opening. 

Tumours. 

Solid tumours of the conjunctiva may be divided into 
congenital (Dermoid, Lipoma, Nsevus) and acquired. The 
latter are benign (Papilloma, Angioma, Lymphoma, etc.) or 
malignant (Epithelioma, Sarcoma). 

*Dermoid Tumours. — -These are pale yellow or white in 

colour, and in size from that --- -. 

of a split pea to that of a 

cherry. They are smooth on 

the surface, dry looking, and 

sometimes have fine hairs, 

and sit usually at the outer 

and lower margin of the 

cornea ; but in the case 

illustrated by Fig. 104 it was 

situated on the inner side 

. . ,. Fig. 104. 

oi the cornea, extending 

over somewhat on the latter, and not at the most usual seat. 
In structure they resemble that of the skin. 

13 




194 



DISEASES OF THE EYE. 



[chap. v. 



They often increase in size at puberty, and the hairs 
then grow. They are congenital tumours, supposed to be 
due to an arrest in development, but they often have a 
tendency to extend over the cornea. If this tendency be 
present, the tumour must be removed by dissecting it off 
the cornea, care being taken not to go into the deep layers 
of the latter. 

*DermO-Lipoma occurs as a fibro-fatty congenital tumour, 
usually situated between the superior and external recti 
muscles. Pure lipoma is exceeding rare. Fig. 105 represents 

a dermo-lipoma in an nn- 



4^ 



FiG. 105. — Dermo-lipoma 
with hairs. 



usual situation. The patient 
sought relief on account 
of the irritation caused 
^jjp ■ by the long hairs which 

were only noticed about 
puberty. 

Osteoma is a very rare con- 
genital tumour, which occurs 
in the same situation as the 
dermo-lipoma. 

*NsevuS (or Mole). — This congenital usually pigmented 
growth appears most commonly at the limbus, as a brown 
spot, or as a fiat gelatinous looking swelling, of a brown or 
reddish colour. It may be stationary, or may become 
progressive at puberty. The pigmented variety occasionally 
forms the starting-point of a pigmented sarcoma. Micro- 
scopically a conjunctival na?vus consists of epithelial down- 
growths combined with groups of smaller so-called nrevus 
cells, the origin of which is doubtful. Cases which have 
been described as benign epithelioma and dermo-epithelioma 
were most probably unpigmented najvi. 

Treatment. — If the nrevus be disfiguring or progressive it 
can easily be excised. 

*H8emangioma (Vascular Nsevus). — This is generally 



CHAP. V.] 



THE CONJUNCTIVA. 



195 



met with in young people and is often congenital, but is 
sometimes the result of injury. It may be capillary or 
cavernous and is liable to increase in size. It occurs along 
with the same condition of the lids, but also separately, 
especially on the plica or caruncle. 

Treatment. — Electrolysis or ligature;. Good results have 
been obtained by Snell with ethylate of sodium carefully 
painted on. 

*PolypUS and Granuloma. — True mucous polypi never 
occur on the conjunctiva. The growths, to which the name 
of polypus is given, are tumours of different kinds which 
become pediculated owing to the movements of the lids and 
eyes ; they are fibromata or papillomata. Granulomata, or 
granulation tissue, occurring after operations (squint, 
enucleation, chalazion) or produced by foreign bodies, or 
even tuberculosis, may also assume a polypoid form. The 
soft fibromata are sometimes the cause of bloody tears. 

*Lymphoma.- — Diffuse lymphoma of the conjunctiva occurs 
in leukaemia or pseudo-leukaemia, but also as a primary 
affection, which is probably an early stage of amyloid 
disease (see Pigs. 101 and 102). 1 Small lymphomatous or 
lymphosarcomatous tumours are met with rarely, chiefly at 
the inner canthus. Some of the cases described as lymphoma 
were examples of Parinaud's disease. 

* Papilloma, or Papillary Fibroma. — This is a non- 
malignant growth, which may spring from any part of the 
conjunctival sac. It may occur at any age, and several 
tumours may be present. It is much more common in men 
than in women. It appears in the beginning as a small 
round red knob. The papillomata growing from the tarsal 
conjunctiva and from the semi-lunar fold frequently take on 
a cauliflower appearance ; while on the bulbar conjunctiva 
and in the fornix the growths are liable to be pedunculated, 
with a papillary surface. The limbus of the conjunctiva is 



1 Trail*. Oph, Hoc. U. 11., xxiv., p. 24. 



196 



DISEASES OF THE EYE. 



[chap. v. 



a favourite seat for a papilloma (Fig. 106,) and in the early 
stage it may be impossible to distinguish it from an 
epithelioma. But at a later stage, when the growth has 
overlapped the cornea, the papilloma merely overlies it and 
can be lifted freely off it with a probe, while the epithe- 
lioma, as a rule, infiltrates the corneal tissue. Moreover, 
enlargement of the pre-auricular gland only occurs in the 




FIG. 106. — Papilloma growing- at the limbus. 
Sketched by L. W. 

latter. But it must be remembered that papillomata in 
elderly people sometimes become malignant. 

Treatment. — Thorough removal with knife or scissors, 
followed by the use of actual cautery, as otherwise the growth 
is liable to recur. 

*Malignant Tumours (Epithelioma, Sarcoma).— These 

rare growths generally take their origin in the limbus, 
most frequently at the temporal side. They are often 
extremely slow in their growth, lasting perhaps several years 
before attaining any considerable size. They are epibulbar 
tumours, that is to say they spread on the surface of the 
eyeball and very rarely penetrate it. They may be pigmented 
or not. The pigmentation is explained by the fact that the 
limbus contains pigment, although generally so slight in 
amount as not to be visible to the naked eye. There is no 
cachexia, and the liability to metastases is much less than 



CHAP. V.] 



THE COyJUNCTIVA. 



197 



in the case of intraocular growths, but the tendency to 
recurrences is very great. The disease is rarely met with 
under forty years of age. On account of the alveolar struc- 
ture so often present in these tumours, differences of opinion 
not infrequently arise in the effort to distinguish between 
sarcoma and epithelioma. The tumour soon becomes sur- 
rounded by a localised congestion and, as it grows, it 
interferes with sight and prevents closure of the lids, but 
does not cause much pain until the later stages, when 
ulceration and haemorrhage are apt to occur. 

Epitheliomala are usually non-pigmented and at first may 
be mistaken for phlyctens — of which, however, the margins 
are not so steep — or for papillomata {vide supra). The 
surface is wart-like or papillary, or it may be nodular, but the 
nodules are not so smooth nor so large as in a sarcoma. The 
cornea becomes infiltrated by the growth and the lymphatic 
glands may be enlarged. 

Sarcomata on the other hand are generally pigmented, 
the tumour is smooth or nodular, and rarely polypoid, and 
is not adherent to the cornea, or at least does not involve 
it except in a very late period. 

But conjunctival sarcoma also starts from other parts of 
the conjunctiva, and in a case at the Royal Victoria Eye 
and Ear Hospital sarcomatous tumours were four times 
removed from different parts of the fornix, an interval of 
some months elapsing between the appearance of each small 
tumour, and finally enucleation became necessary. 

Treatment. — Both epithelioma and sarcoma of the conjunc- 
tiva demand prompt operative removal, in order to prevent 
an extension of the growth to the rest of the eye, as well 
as to avert metastases to other organs. The knife and 
actual cautery may save the eye and the patient's life in 
the early stages. When a recurrence takes place it is safer 
to remove the eye, more especially if the patient cannot be 
kept under constant supervision. 



CHAPTER VI. 



PHLYCTENULAR CONJUNCTIVITIS, AND 
KERATITIS.' 

Both from a clinical and nosological point of view it would 
be incorrect to divide this affection into two, under the heads 
of Diseases of the Conjunctiva and Diseases of the Cornea ; 
and therefore it is treated of here as one disease, and, being 
a very important disease, a special chapter is given to it. 
It is important, because it is excessively common, and be- 
cause it is capable of causing considerable damage to sight. 
Moreover, even when it occurs on the cornea, it might, 
strictly speaking, be regarded as a conjunctival disease, for 
that corneal layer, which it primarily attacks, is the epithelium, 
and this — and probably also Bowman's membrane and the 
anterior layers of the true cornea — as we know from 
the foetal development of the membrane, is a continuation 
of the conjunctiva in a modified form over the cornea. 2 

The disease is characterised by the eruption of phlyctenular 
(^iXvKraiva, a vesicle, or pustule) on the conjunctiva bulbi, 
on the conjunctival limbus, or on the cornea. It is chiefly 
a disease of children up to the eighth or tenth year of age, 
except that it may be said not to occur in the first year 



1 K^pas, a horn. 

- The posterior epithelium -or, according to some, this along with 
the membrane of Descemet and the posterior layers of the true cornea 
—is to be reckoned to the uveal tract; while the true cornea is a 
modification of the sclerotic. 

1!)8 



CHAP, vi.] PHLYCTENULAR OPHTHALMIA. 



199 



of life. It is seen occasionally in adults, and especially 
in women. 

Notwithstanding the derivation of the word, a phlyctenula, 
or phlyctene, is originally neither a vesicle nor a pustule. 
It is. a formation sui generis, and, when on the conjunctiva, 
is a solid elevation consisting of a collection of lymph cells, 
and is of a greyish colour. In a late stage the phlyctenula, 
especially on the cornea, may become a pustule by infec- 
tion. On the conjunctiva two types of the disease can be 
recognised : — 

1 . The Solitary, or Simple, Phlyctenula. — Of this there 

may be one or several, varying in size from 1 mm. to 4 mm. 
in diameter. The vascular injection is immediately around 
the phlyctenula, and is not diffused over the conjunctiva, yet 
it is true that occasionally any form of phlyctenular disease 
may be associated with simple conjunctivitis, which is to 
be regarded as secondary to the phlyctenular affection. At 
first there may be shooting pains and lacrimation, but these 
soon pass away. If the phlyctenular be not seated close to the 
cornea the affection is not serious ; and the length of time 
required for its cure depends on the size of the phlyctenula?, 
varying from seven to fourteen days, as a rule. 

2. Multiple, or Miliary, Phlyctenulae.— These are very 
minute, like grains of fine sand, and are always situated on 
the limbus of the conjunctiva, which is swelled. The general 
injection and swelling of the conjunctiva are considerable ; and, 
occurring as it does almost exclusively in young children, the 
affection may be called Eczematous Conjunctival Catarrh of 
Children (Horner). The irritation and so-called photophobia 
and lacrimation are often considerable, and there is a good deal 
of conjunctival catarrh. This form is very apt to appear 
after measles and scarlatina. 

lUjth far in* >n-<- liable to extend to the cornea, and then only 
does the disease become serious. This event may come about 
in the following different ways: — 



200 



DISEASES OF THE EYE. 



[CHAP. VI. 



The Solitary Phlyctenula may be seated partly on the 
limbus conjunctivae and partly on the margin of the cornea, 
and may undergo resolution. 

Or it may give rise to a deep ulcer, which either heals, 
leaving a scar, or perforates, causing prolapse of the iris, etc 

Or it may form the starting-point of a fascicular keratitis, 
the pustule becoming an ulcer, at the margin of which the 
corneal epithelium is raised and infiltrated in crescentic shape. 
This now steadily advances for many weeks towards the centre 
of the cornea, followed by a leash of vessels which has its 
termination in the concavity of the crescent. The process is 
accompanied by much irritation of the terminal branches of 
the fifth nerve in the cornea, and the consequent reflex 
blepharospasm. A permanent mark indicates the track of 
the ulcer. 

The Multiple Miliary Phlyctenule on the limbus conjunc- 
tivas may cause some slight superficial infiltration and vascu- 
larisation of the cornea in their immediate neighbourhood, 
which pass off when the phlyctenule disappear. 

Or they may be accompanied by deeper marginal infiltra- 
tions of the cornea, which become confluent and result in an 
ulcer that extends along the margin of the cornea for some 
distance, and is termed a Ring Ulcer. It is a serious form 
of ulcer ; for if it extend far round it may destroy the cornea 
in a few days by cutting off its nutrition. 

Primary Phlyctenular Keratitis occurs principally in 

three different forms: — (1) Very small grey sub-epithelial in- 
filtrations, which are apt to result in small ulcers, and then 
heal, leaving a slight opacity. This opacity may ultimately 
quite disappear, especially in the case of children, and when 
situated peripherally. (2) Somewhat larger and deeper in- 
filtrations, resulting in ulcers of corresponding size, which 
heal by aid of vascularisation from the margin of the cornea. 
The opacity left after these ulcers is rather intense, and clears 
up but little, especially if the situation be central. (3) Large 



chap, vi.] PHLYCTENULAR OPHTHALMIA. 



201 



—77 



and deep-seated pustules, due to secondary infection, often at 
the centre of the cornea, giving rise to large and deep ulcers, 
which may be accompanied by hypopyon and even by 
iritis, and which fre- 
quently go on to 
perforation. 

Photophobia is 
usually a prominent 
symptom in phlyc- 
tenular keratitis. 
The term photo- 
phobia, however, is 
not altogether cor- 
rect, for it is the 
fifth nerve (from the 
cornea) which is 
mainly the afferent 
nerve here rather than the optic nerve. This is evident 
from the fact that in the dark the patient does not get 
complete relief. The explanation of this reflex blepharospasm 
has been given by Iwanoff, who showed that the round cells, 

their way 




FIG. 107. — E, Epithelium ; B, Ant. elastic 
Lamina ; C, True Cornea N, Nerve Filament, 
with Lymph Cells on its course ; I), Phlyc- 
tenula. 



in 



B — 




making 



- D 



from the margin of the 
cornea to their position 
under the epithelium, 
follow the course of 
the nerve filaments, 
which they irritate 
in their progress. The 
accompanying Figs. 107 
and 108 are from his original paper. 

Enlarged cervical glands, eczema of the eyelids, face, and 
external ear, and catarrh of the Schneiderian mucous mem- 
brane, frequently accompany phlyctenular conjunctivitis and 
keratitis. 



202 



DISEASES OF THE EYE. 



[chap. VI 



In these cases, in children of three or four years of age, 
temporary amaurosis has sometimes been observed after a 
severe and long-continued blepharospasm has passed away. 
The patient is found to be unable to see even large objects, 
or to find his way, although the pupil-reflex is active, and 
a strong light may still be distressing. There are no 
ophthalmoscopic appearances. This blindness passes away 
completely, usually in from two to four weeks, although the 
interval before recovery of sight may be several months. A 
certain mental dulness, which also ultimately disappears, is 
noticed in some cases. This temporary loss of sight has been 
regarded as a reflex phenomenon, and again it has been held 
to be due to disturbance of the intraocular circulation from 
pressure of the eyelids on the eyeball. But the view (Leber, 
Uhthoff) which represents it as having a cerebral origin of 
a functional nature is probably the correct one. It is likely 
at this tender age, when the psycho-physical processes are 
not as yet firmly established, that the desire not to see, and 
the active withdrawal from the act of vision, leads in a short 
time Lo a functional paralysis of the visual centres in the 
brain, and that these take some time to recover, or to re-learn, 
their functions, when the ground for the suspension of the 
latter has ceased. 

As a result of frequent relapses of phlyctenular keratitis, 
a superficial pannus-like vascularisation may form in the 
cornea, in those regions of it which have been chiefly 
attacked. 

Cause. — As already stated, this is a disease of childhood, 
although it is extremely rare in the first year of lifo. In 
adults it is uncommon. 

The strumous constitution — as indicated by the swollen nose 
and upper lip, and sometimes by the enlarged lymphatics iD 
the neck, and by the eczema — allied to tuberculosis, is that 
most liable to this affection. Often, however, it will be 
found in strong children with apparently perfect general 



chap, vi.] PHLYCTENULAR OPHTHALMIA. 



203 



health ; but even in them there is probably some irregularity 
of nutrition, of which the great tendency to recurrence of 
the eye affection is evidence. 

Colonies of straw-coloured micrococci may be found in the 
contents of the phlyctenular ; but what, if any, etiological 
relationship they have to the production of the latter is 
unknown. 

Treatment. — The solitary phlyctenula of the conjunctiva 
is best treated with a 2 per. cent, yellow oxide of mercury 
ointment, of which the size of a hemp-seed should be put 
into the eye with a small glass rod, once a day. To obtain 
the best result with this ointment, its base should consist of 
10 parts of pure white vaseline, and one part each of 
anhydrous lanoline and water. The yellow oxide is to be 
freshly precipitated and in very fine powder, and when it 
has been well rubbed up with the water, the anhydrous 
lanoline and vaseline are added. This ointment contains no 
fatty substance, and consequently mixes with the tears and 
comes thoroughly in contact with the surface of the eye. 
Ordinary lanoline contains olive oil. The ointment should 
not be unnecessarily exposed to light or air. Or, a small 
quantity of pure calomel dusted into the eye once a day will 
also cure ; but this remedy should not be employed if iodide of 
potassium is being taken internally, for then iodide of mercury 
is liable to be formed in the conjunctiva. 

The miliary phlyctenular conjunctivitis may be treated at 
first with cold or iced applications. Freshly prepared chlorine 
water (1 part Liq. Chlori., 9 parts water), to be dropped into 
the eye once a day, is recommended by some, and later on 
Liq. plumbi dil. or Sol. argent, nitr. (gr. v ad 3j> an d 
neutralised) applied to the everted conjunctiva ; or, if the 
phlyctenular appearance predominate over the catarrhal, the 
yellow oxide of mercury ointment or insufflations of calomel 
may be preferred. Indeed, practically, the two latter 
remedies are applicable in all these cases. 



204 DISEASES OF THE EYE. [chap. vi. 



When the cornea is slightly affected near the margin in 
cases of miliary phlyctenular, calomel, or the yellow oxide of 
mercury ointment, and warm fomentations, should be used. 

Where a large pustule on the margin of the cornea has 
resulted in a deep ulcer, with tendency to perforate, and 
accompanied by much pain, paracentesis of the anterior 
chamber through the floor of the ulcer, the pupil having 
first been brought well under the influence of eserine to 
prevent prolapse of the iris, cannot be too strongly advocated. 
The good effect of this will be very soon apparent : the pain 
disappears, the patient sleeps, the ulcer becomes vascularised, 
and healing sets in. Cauterisation of the ulcer in an early 
stage with the galvano-cautery is also good practice ; but in 
these cases paracentesis is preferable. Many surgeons trust 
too much to eserine, warm fomentations, and a pressure 
bandage. 

For the fascicular keratitis the yellow oxide of mercury 
ointment is again in its place. When the crescentic infiltra- 
tion is very intense it is well to touch it with the galvano- 
cautery. 

For the ring ulcer a pressure bandage, under which an 
antiseptic dressing (boric or salicylic acid, or perchloride of 
mercury) has been placed, is, perhaps, the best method of 
treatment. Warm fomentations promote vascular reaction, 
and may be used with benefit at each change of bandage. 

For primary phlyctenular of the cornea, in the form of the 
minute grey superficial infiltration or ulcer, nothing beyond 
atropine, with warm fomentations, and a protective bandage 
to keep the eyelids quiet, should be used. When reparation 
of the ulcer has commenced, calomel or weak yellow oxide 
of mercury ointment may be employed. 

For the large infected phlyctenula, resulting in a large 
and deep ulcer, often situated at the centre of the cornea, 
with hypopyon and iritis, warm fomentations (camomile, or 
poppy-head, at 90° Fahr., for twenty minutes three times 



chap, vi.] PHLYCTENULAR OPHTHALMIA. 



205 



a day), atropine, <boric acid as ointment or powder, and a 
protection bandage form the treatment in the early stages. 
Here, also, the ulcer may be punctured with the very best 
results in respect of hastening the cure, or the galvano- 
cautery may be used with advantage. In the stage of re- 
paration the yellow oxide of mercury ointment or insufflations 
of calomel are very useful. 

In nearly all cases of phylctenular keratitis dionine 
(5 per cent, solution) aids the cure. 

In all forms of phlyctenular ophthalmia those favourite 
remedies, blisters, setons, and leeching, should be avoided. 
The first two worry the patient, give rise to eczema of the 
skin, and are not to be compared in their power of cure with 
the measures above recommended ; while leeching gives, at 
best, but temporary relief, and deprives the patient of blood 
which he much requires. 

For relief of the blepharospasm, in addition to the use of 
atropine, plunging the child's face into a basin of cold water 
is a most efficacious means. The face is kept under the 
water until the child struggles for breath, and this immer- 
sion is repeated two or three times in rapid succession, and 
used every day if necessary. It should always be used 
where the blepharospasm is severe, as the latter is not only 
distressing to the patient, but also an obstacle to the cure. 

The general treatment, notwithstanding the so-called photo- 
phobia, should consist in open-air exercise before everything 
else, unless, indeed, there be an ulcer which threatens to 
perforate. It is not well to keep the eyes (unless there be 
a corneal ulcer) or patient's face covered with bandages and 
shades, nor to confine him to a dark room. A pair of dark- 
blue glasses are the best protection from strong glare of 
light ; and shady places can be selected when the patient 
is out of doors. Cold or sea baths, followed by brisk dry 
rubbing. Easily assimilated food at regular meal hours, 
but no feeding between meals. Regulation of the bowels. 



206 



DISEASES OF THE EYE. 



[CHAP. VI. 



Internally : cod-liver oil, maltine, iron, arsenic, syrup of the 
phosphate of lime, and such-like remedies are indicated. 

The great tendency to recurrence is one of the most trouble- 
some peculiarities of all kinds of phlyctenular ophthalmia; 
and in order to prevent this, so far as possible, it is im- 
portant, not only to improve the general health, but also 
to continue local treatment until the eye is perfectly white 
on the child's awaking in the morning, and even for fourteen 
days longer. This prolongation of the treatment will also 
assist in clearing up opacities, as best they may be. For 
this after-course of treatment calomel insufflations should 
be used. 

Nothing can be done for the opaque scars left on the cornea 
by idcers when all inflammatory symptoms have subsided. 
If the ulcer have been very superficial the resulting scar in 
young children may disappear in the course of time. Deep 
ulcers cause more opaque and permanent scars, and ulcers 
which have perforated produce the greatest opacity. Some 
of the very disfiguring scars may be tattooed (see chap. vii.). 

The degree of the defect of vision to which an opacity of 
the cornea may give rise depends, in the first instance, on the 
position of the opacity. If it be peripheral, the vision may be 
perfect ; but if it be in the centre of the cornea, sight may 
be seriously damaged. Even a slight nebula, barely visible to 
the observer, will cause serious disturbance of vision if situated 
in the centre of the cornea ; while in the same situation the 
very opaque scar of a deep ulcer will produce a proportionately 
greater defect. If a central, but not deep, ulcer should not 
become completely filled up in healing, and a facet remain, 
vision will also suffer much in consequence of irregular refrac- 
tion, although there may be but little opacity. 



CHAPTER VII. 



DISEASES OF THE CORNEA. 

The importance of a knowledge of the diseases and injuries 
of the cornea depends on their great frequency, coupled with 
the fact that nearly every one of them is liable to leave 
behind it some opacity, with resulting defect of sight and 
disfigurement of the eye ; while several of them are very apt 
to lead to complete loss of sight. 

Clinical Methods of Examining the Cornea. 

1. By Diffuse Daylight. The patient having been placed 
with his face towards the window, the cornea is carefully in- 
spected. The patient is required to keep both eyes open, 
while his upper lid is gently raised with the surgeon's thumb, 
and to direct them upwards, downwards, to the right, and 
to the left, so that every part of the affected cornea may 
be seen under the most favourable and varied incidence of 
the light. Should there be much reflex blepharospasm, 
the instillation of cocaine, by producing anaesthesia of the 
cornea, assists the examination. With small children it is 
often necessary to adopt the plan illustrated by Fig. 91. 

2. By Focal, or Oblique, Illumination. In the dark room 
the light of the ophthalmoscope lamp is focussed with a 
+ 14 0 lens on the cornea, which is thus seen brilliantly 
lighted up. The lamp must be placed in front of and 
slightly to the left-hand side of the patient, and about two 
feet from his eye. The lens is placed between the lamp 

207 



208 



DISEASES OF THE EYE. 



[CHAP. VII. 



and the eye, so that the light may be concentrated by it 
on the cornea. 

3. By the Combined Focal Method, that is focal illumination 
as above, combined with the use as a magnifying-glass 
of a second + 14-0 lens. The second lens is held between 
the finger and thumb of the left hand some inches from 
the patient's eye, while the surgeon places his eye at the 
focus of the glass, the cornea being at the same time 
illuminated by the light focussed on it with the other lens 
held between the finger and thumb of the right hand. 
Changes in the cornea are then seen magnified, and at the 
same time highly illuminated. 

4. By the Ophthalmoscope with a +18 0 or +20 0 lens 
behind the sight-hole of the mirror. The surgeon proceeds 
as though he were about to examine the fundus in the 
erect image. The cornea is illuminated from the mirror, 
and changes in it are magnified by the + lens through 
which it is inspected. 

5. By Fluorescine. In cases of ulcer, or any abrasion of 
the corneal epithelium, when it is desired to ascertain 
accurately the whole extent of the loss of substance, or if 
there be some hesitation as to the presence of such a lesion, 
an instillation of a drop of fluorescine solution (Fluorescin. 
gr. ij, Sodii Carb. gr. j, Aq. destill. 3 ij) is used. About 
half a minute after the instillation, the whole region which 
is denuded of epithelium will be seen stained of a greenish 
yellow colour. In some instances where there is no true 
loss of substance, staining takes place if the epithelium 
be not sound. An ulcer, which in the process of healing 
has become covered with sound epithelium, will not stain, 
although there may still remain some loss of substance to be 
filled up. Fluorescine does not harm the cornea, nor inter- 
fere with healing of any diseased process in it, and the 
staining passes away after a short time. 

The foregoing methods are in everyday use. 



CHAP. VII.] 



THE CORNEA. 



209 



6. By the Corneal Microscope. This is an elaborate optical 
instrument, which forms the outfit of a well-equipped 
ophthalmic hospital, for the minute study of diseased states 
of the cornea and iris. It is not needed for ordinary 
clinical work, and therefore a description of it will not be 
given here. 

Inflammations of the Cornea. 

From a clinical standpoint these inflammations will be 
most conveniently considered under the headings — («) Ulcera- 
tive Inflammations, and (6) Non-ulcerative Inflammations. 

(a) Ulcerative Inflammations of the Cornea. — Before an 
ulcer can form in the cornea there must be a cellular infiltra- 
tion of its tissue near its anterior surface ; and this cellular 
infiltration is brought about, in most instances, if not in all, 
by the entrance into the cornea of certain micro-organisms, 
pneumococci, diplobacilli of Morax, staphylococci, streptococci, 
bacillus subtilis, etc. One recognises the existence of an infill 
tration by seeing an opaque spot in the cornea, with a dulness 
of the layers over it, and often of the corresponding part of 
the epithelium. Before long the epithelium covering the in- 
filtration undergoes necrosis and comes away, and soon the 
intervening layers of the true cornea also break down, and 
in this way an ulcer becomes established. 

But although all ulcers of the cornea originate in an in- 
filtration, yet, once established, they assume great varieties 
of type, in consequence, probably, of a variety in the nature of 
the originating micro-organisms. Some ulcers are purulent, 
others non-purulent ; some tend to spread over the surface of 
the cornea, others tend to go deep into it ; the progress of 
some is very rapid, and of others exceedingly chronic ; some 
attack by preference the central region of the cornea, while 
others are confined to its margin ; some readily give way to 
treatment, and others are very obstinate or almost incurable. 

H 



210 



DISEASES OF TTIE EYE. 



[chap. vii. 



Again, some ulcerative corneal processes are attended by much 
irritation: that is to say, circum-corneal injection, severe 
pain in and about the eye, great reflex blepharospasm, and 
lacrimation ; whilst others, which may really be more severe 
processes in so far as the integrity of the eye is concerned, 
can run their course with hardly any injection of the eye- 
ball, and with little or no distress to the patient. 

Etiologiccdly, corneal ulcers are primary or secondary. The 
primary ulcers are those in which the diseased process 
originates in the cornea, most commonly as the result of 
traumata, but also in phlyctenular keratitis, or as the result 
of corneal abscess, or where the nutrition of the cornea is 
interfered with, etc. Secondary ulcers are those which are 
the result of disease elsewhere, usually in the conjunctiva, as 
in acute blennorrhoea and in conjunctival diphtheritis. 

Corneal ulcers are more common in advanced than in early 
life. Indeed, in early life, unless in cases of infantile ulcera- 
tion with conjunctival xerosis, of blennorrhoea neonatorum, 
and of phlyctenular disease, corneal ulcers are almost un- 
known. The greater liability to these affections in advanced 
life is due, it may be assumed, to a less active nutrition 
at that period in this already lowly organised part. Hence 
slight traumata, or the presence of a slight conjunctival 
catarrh, which would have no ill effect in a young person, 
may form the starting-point of a corneal ulcer in an old 
person, or even in one of middle age. For the same reasons, 
corneal ulcers are much more common in the poorer classes 
than amongst the well-to-do ; for their general nutrition 
is often defective, while they are more exposed to traumata 
than are the better classes. 

The Diagnosis of the presence of a large corneal ulcer is 
simple. Inspection of the cornea in ordinary daylight at 
once reveals the loss of substance, more or less extensive, 
deep, or infiltrated. If the ulcer be very small and shallow 
the difficulty is greater, especially if there be much blepliaro- 



CHAP. VII.] 



THE CORNEA 



211 



spasm. An instillation of cocaine may be necessary to facili- 
tate the examination. 

It is obviously important to decide at the outset, for the 
purposes of prognosis and of treatment, whether a grey spot 
in the cornea be an infiltration (a collection of cells which 
may shortly break down and become an ulcer), an ulcer, or a 
scar (the result of an ulcer, or other loss of substance). The 
surface covering an infiltration, although flush with the general 
surface of the cornea, has usually a steamy appearance, due to 
disorganisation of the corneal epithelium, and has no lustre. 
With an ulcer the appearances already described will be found. 
The surface of a scar is usually, although not always, flush 
with the general surface of the cornea, and it has a bright 
surface — i.e., covered with normal epithelium, not rough, 
irregular, nor even steamy. In cases of corneal infiltration, 
or ulceration, there will be usually more or less pericorneal 
injection, pain, and photophobia, while with a mere corneal 
scar there will be no irritation of the eye. Fluorescin 
stains an ulcer, and sometimes an infiltration if it be near 
the surface, but not a cicatrix. 

The presence of Hypopyon (viro, under ; irvov, pus) is the 
rule with several types of corneal ulcer, notably the deep 
ulcer, and the serpiginous ulcer. The term ' hypopyon 
ulcer,' which is so much used, should certainly be discarded, 
as hypopyon ia not the characteristic of one type of ulcer. 
Hypopyon is a deposit of pus in the anterior chamber, and 
as the patient sits or stands it lies in the lowest part of the 
chamber, to which place it has gravitated. If the patient lie in 
bed, say on the side of the affected eye, the hypopyon will of 
course change its position, and gravitate towards the temporal 
side of the chamber. Sometimes the hypopyon is so small as 
to be detected with difficulty ; and again it may fill the whole 
anterior chamber, completely obscuring the iris and rendering 
a diagnosis of the condition of the cornea difficult. It will be 
asked, From whence does the pus come which forms hypo- 



212 



DISEASES OF THE EYE. 



[chap. vii. 



pyon in cases of corneal ulcers ? It might be supposed that 
it is derived directly from the purulent floor of the ulcer, 
by passage of the pus-cells through the posterior layers of the 
cornea. But this is not so. No pus-cells do, or indeed can, 
pass through the membrane of Descemet. Moreover, copious 
hypopyon is often present, when the corneal ulcer is quite 
small and non-purulent. The pus-cells, which form hypopyon 
in cases of corneal ulcer, come from the iris, in compliance 
with the law which causes leucocytes to wander out of blood- 
vessels in the neighbourhood of an inflammatory focus, and 
to make their way towards that focus. When these leucocytes 




Fig. 109 (Fuclis). 



from the iris reach the anterior chamber they can go no 
farther, owing to the barrier imposed to their progress by 
the membrane of Descemet. The pus forming a hypopyon 
is sterile. 

The Dangers attendant upon Corneal Ulcers are, first of all, 
the opacities, the scars, which even the slightest of them are 
apt to leave behind. 

Fig. 109 represents a section made through a deep ulcer 
in its progressive stage. At the margin of the ulcer the 
epithelium (e) and Bowman's membrane (b) cease. The floor 
of the ulcer is seen covered with pus, which also infiltrates 
the corneal tissue beneath the floor and around the margin. 



CHAP. VII.] 



THE CORNEA. 



213 



As soon as cure commences the floor of the ulcer begins to 
clear, i.e., it becomes gradually less covered with pus, until it 
is finally quite free from it, and pari passu the surrounding 
infiltration of the cornea is absorbed. Then the epithelium, 
growing in from the margin (to to, Fig. 110) all around, 
gradually carpets over the floor of the ulcer, and under- 
neath this newly formed epithelium the new tissue, which 
is to close in the loss of substance, is laid down. This new 
tissue, however, is not normal corneal tissue, but is ordinary 
connective tissue, and is therefore opaque. Hence the 




Fig. 110 (Fuclis). 



deeper the ulcer, the more intense will be the resulting 
opacity. Bowman's membrane never becomes restored over 
the cicatrix. 

The ulcers which are situated at the centre of the cornea, 
in the pupillary area, are more serious for sight than those 
situated peripherally, as can be readily understood. The 
opacity left by a very superficial ulcer is slight, and is 
called a nebula ; a somewhat more intense opacity is 
called a macula ; and a very marked white scar is called a 
leucoma. 

But a more serious danger connected with ulcers of the 
cornea than the opacities they leave behind is that of per- 



214 



DISEASES OF THE EYE. 



[CHAP. VII. 



foration of the cornea, to which some ulcers are very prone. 
The consequences of perforation are prolapse of iris, re- 
sulting in anterior synechia?, adherent leucoma, or staphyloma 
of the cornea (see pp. 150, 151, 217, 253), and fistula of 
the cornea (p. 223). 

Treatment. — In the treatment of primary corneal ulcers 
the student will soon observe that a bandage, atropine, and 
warm fomentations play prominent parts ; and these routine 
measures alone ai'e sufficient to produce cure in the less 
severe cases. 

The bandage should be put on with firm pressure, — but 
should not be made uncomfortably tight, — the eye having been 
previously padded out, especially at the inner canthus, so 
that equal pressure may be exercised on the globe all over. 
The support thus given to the cornea and front of the eye 
promotes the healing process, and the bandage is also use- 
ful by preventing the eyelids from rubbing over the ulcer, 
and by protecting it from foreign bodies. In those 
secondary ulcers, which are due to conjunctival processes, 
such as catarrhal conjunctivitis or blennorrhcea, a bandage 
is contraindicated, because it retains the secretion, and 
would therefore do harm rather than good. 

Atropine in sufficient quantities to keep the pupil dilated 
should be employed. Iritis very often attends severe corneal 
ulcers, and here the indication for atropine is obvious. But 
rest of the affected part is, we know, an important element 
in preventing or in curing any inflammation ; and in the 
affections we are now treating of, even if there be no 
iritis, atropine acts by procuring rest of the iris and of 
the ciliary muscle, the constant motion of which would 
otherwise tend to augment the inflammatory process in 
the cornea. 

Myotics are preferred by some to mydriatics in the treat- 
ment of corneal ulcers, on the ground that the action of 
myotics in reducing the intraocular tension promotes healing, 



chap, vii.] THE CORNEA. 215 



and that the more extended surface of iris — more extended 
absorbing surface — facilitates absorption of hypopyon. It is 
not certain that myotics do reduce the normal tension, and 
in these cases they undoubtedly increase the tendency to 
iritis. As to absorption of the hypopion it will come about 
in due course when the cornea begins to recover. Yet a clear 
indication for myotics is given by the presence of an ulcer 
near the corneal margin, which has a tendency to perforate, 
for here the myosis would assist in preventing prolapse of 
the iris, should perforation take place. 

Dionine is useful in the treatment of many cases of 
primary corneal ulceration and other primary corneal diseases. 
Its physiological action is to cause dilatation of the lymphatic 
vessels of the conjunctiva with great chemosis, although it 
does not act equally in every eye, and its therapeutic effect 
is held to depend on this lymphatic flooding of the front of 
the eye. It is used in a 5 per cent, solution dropped into 
the eye once or twice a day. If employed frequently it ceases 
to produce any reaction, and for this reason it may be 
desirable in some cases to use it once only on alternate days. 
It causes slight ansethesia of the cornea. 

Warm fomentations promote the healing process by stimu- 
lating tissue-changes in the cornea. One usually orders 
them to be made with poppy-head water or camomile tea, 
although no doubt warm water would be equally efficacious. 
Hot solutions of 4 per cent, boric acid, or 1 in 5000 corrosive 
sublimate, may be used with advantage. The bandage having 
been removed, a compress of cotton wool which has been 
dipped in the stupe at about 120° Fahr. is laid upon the eye, 
and frequently replaced by fresh compresses out of the 
stupe, so that the compress on the eye may always be hot. 
Th is i.s continued for half an hour at a time, and repeated 
every two or three hours. Or, the Japanese muff-warmer 
may be applied. 

In an ulcer of a purulent or sloughing nature, the 



216 



DISEASES OF THE EYE. 



[chap. vii. 



insufflation on its floor of very finely divided 
xeroform powder is useful. 

When more active measures than the fore- 
going are called for, the actual cautery, 
curetting, paracentesis, and subconjunctival 
injections have to be resorted to. 

The actual cautery is much in use in the 
treatment of serpiginous and other infected 
corneal ulcers. It acts by destroying the micro- 
organisms, which keep the process going. 
Either a thermo-cautere, in the form of a very 
fine point, or the galvano-cautery (Fig. 11), 
the platinum wire being at a red-heat, may be 
employed. The eye having been cocainised, 
the red-hot point is brought into contact 
with the whole surface of the ulcer, so as to 
thoroughly destroy its superficial layer, and 
special attention is given to any part of the 
margin of the ulcer where there is a tendency 
to spread to as yet healthy tissue. Fluorescine 
may be used to show the exact extent of the 
ulcerated surface. The cauterisation can be 
repeated as often as the state of the ulcer 
may make it desirable. It is sometimes well 
to perforate the cornea with the cautery, and 
to evacuate the aqueous humour and hypo- 
pyon ; or this may be done with an ordinary 
paracentesis needle, after the cauterisation is 
completed. The cautery gives a good per- 
centage of cures with ' the least amount of 
opacity. 



Fig. 111. 



FIG. 111. — The bolt B being pushed forwards, the 
circuit is completed. By pressure on the button A 
the current can be momentarily intercepted during 
use of the instrument. 



CHAP. VII.] 



THE CORNEA. 



217 



Thorough curetting of the floor of the ulcer with a small 
sharp spoon is a valuable method, either alone or prior to 
cauterisation. 

Paracentesis of the anterior chamber through the 
floor of the ulcer is another most valuable therapeutic 
measure for some corneal ulcers, and deserves a more 
routine application in these cases than is accorded to 
it ; the more so as the little operation is simple and 
dangerless. But there are two imperative indications 
for its use, namely : — (1) If there be great pain. 
Soon after the operation, which for a short time in- 
creases the neuralgia, the patient experiences the 
greatest relief, and passes the first good night after 
many wakeful ones. (2) If perforation seem to be 
imminent. This may often be recognised by a bulging 
forwards of the thin floor of the ulcer ; but sometimes 
it is not easily foreseen, and if there be any doubt on 
the point, paracentesis should be performed. It is im- 
portant to forestall spontaneous perforation of the ulcer 
by this proceeding, because the opening that is made 
being linear heals easily, and leaves but a slight scar 
without anterior synechia? ; while the natural opening 
would be a complete loss of substance, and would, 
therefore, the more readily involve adhesion of the 
iris in the resulting, and comparatively extensive, 
cicatrix. Other indications for the operation are 
increased tension, and the presence of a large 
hypopyon. Fig. 112. 

Paracentesis of the anterior chamber is best performed 
by means of a paracentesis needle (Fig. 1 1 2), which is a 
small somewhat shovel-shaped blade. If this be not at 
hand, a small keratome, or a broad needle, or a Grnefe's 
cataract knife will answer the purpose. The eye having 
been cocainised, a spring lid-speculum is inserted, the eye 
fixed with a fixation forceps, and the point of the para- 



218 



DISEASES OF THE EYE. 



[CHAP. VII 



centesis needle applied to the floor of the ulcer, in such 
a way that the plane of the little blade may be at 
an angle of about 45° with that of the floor of the ulcer. 
The point is pushed gently through the floor, and the plane 
of the blade is then immediately changed, so that, as the 
instrument is being advanced up to the hilt, it may be 
almost in contact with the posterior surface of the cornea. 
The instrument should be withdrawn very slowly, in order 
that the aqueous humour may flow off gradually, and not 
with a rush. If these precautions be taken, there need be 
no danger of injury to the crystalline lens, or of prolapse 
of the iris into the incision. Should prolapse occur, it can 
usually be reposed with the spatula. It may happen that 
when the needle has been withdrawn a considerable portion 
of the aqueous humour may remain in the anterior chamber, 
unable to escape owing to the valve-like closure of the wound. 
It should be evacuated by making the wound gape by gentle 
pressure with a spatula on its posterior lip. If it be de- 
sirable to tap the anterior chamber on the next day, this 
can be done by simply opening up the wound with a spatula, 
or with the probe-like instrument at the other end of the 
handle (Fig. 112), without the aid of any cutting instrument. 

Subconjunctival injections of solution of oxycyanate of 
mercury (1 in 5000) or of solution of chloride of sodium (4 
per cent.) enter largely into the therapeutics of corneal disease, 
and of disease in the uveal tract. It is not necessary that 
the injections should be made under the capsule of Tenon 
as was at first supposed. The mode of action of these 
injections is not clearly understood. It is not due to the 
entrance of the preparations into the tissue of the cornea 
or interior of the eye, for only minimal quantities of even 
mercurial salts have been found in the vitreous humour. 
It was at first believed that they acted as lymphagogues, 
but their curative power is now held to depend on the 
vascular reaction to which they give rise. Of the oxycyanate 



CHAP. VII.] 



THE CORNEA. 



219 



of mercury solution 5 to 10 minims according as it can 
be borne, and of tbe saline solution 10 to 20 minims are 
injected under tbe bulbar conjunctiva in tbe direction 
away from tbe cornea. Otber solutions (sublimate, betol, 
cyanate of mercury, iodipin, iodide of potasb, etc.) have 
been employed, but tbese two are as efficacious as any. 
From 2 to 5 minims of a 1 per cent, solution of acoine 
may be taken up in tbe syringe with the main solution, 
just before the injection is made, in order to diminish the 
severe pain and irritation which comes on afterwards and 
lasts often for several hours. This pain may be much 
relieved by hot fomentations, but if it be very intense 
a hypodermic injection of morphia may be necessary. 
Considerable vascular injection and cbemosis may be present 
next day, and the eyelids may be swollen and cedematous. 
The injection should not be repeated until the redness and 
oedema have almost subsided. Few eyes require, or can 
tolerate, more than two injections in the week. (See also 
chap. xi.). 

If the case do not come under the care of the surgeon 
until perforation of the ulcer with prolapse of the iris has 
taken place, the important question as to the best method 
of dealing with the condition is presented. If the loss 
of substance should occupy one third or more of the cornea 
with correspondingly large prolapse of iris, the development 
of a staphyloma is almost inevitable. Eserine is to be used 
to reduce the intra-ocular pressure, and a firm bandage is 
to be kept applied to the eye. And here transplantation 
of conjunctiva over the ulcer and prolapsed iris to strengthen 
the cicatrix (vide, infra) is indicated. But if the ulcer and 
prolapse be small, an attempt may be made to free the iris, so 
that no anterior synechia may form, and in order that the 
cicatrix may be flat, and not raised over the surface of the 
cornea, and, consequently, exposed to injury. The importance 
of such an attempt lies in the fact that a corneal cicatrix with 



220 



DISEASES OF TEE EYE. 



[chap. vii. 



iris entangled in it — not merely adherent to its posterior sur- 
face — affords a constant source of danger, especially if situated 
near the margin of the cornea; for in such eyes, it may be 
years later, sudden and uncontrollable purulent inflammation 
of the iris and chorioid may come on from septic infection 
after an apparently slight trauma of the cicatrix, and rapidly 
end in total destruction of the eye. The surgeon's attention 
should therefore be directed to obtain at least as flat a 
cicatrix as possible, or, still better, a non-adherent cicatrix. 
The practice which is commonly followed, is to draw the 
freshly prolapsed portion of iris slightly forwards with a 
forceps, and to snip it off level with the surface of the cornea ; 
and then with a spatula to endeavour to free the iris from any 
adhesions it may have formed with the margin of the ulcer. 
Atropine or eserine, according to the position of the ulcer, is 
then instilled, and a bandage carefully applied. This pro- 
ceeding is only of use when a fresh prolapse can be dealt 
with, before cicatrisation sets in ; and the result is often 
satisfactory in so far as the securing of a flat cicatrix is 
concerned, but an anterior synechia can rarely be avoided. 

* Da Gama Pinto's method for obtaining a non-adherent 
cicatrix is sometimes useful : — Having abscised the prolapsed 
portion of iris as above, and freed all adhesions to the 
margin of the ulcer with a spatula, he covers the opening 
in the cornea with a flap cut from the bulbar conjunctiva, 
— and this flap should be twice as large as the opening, 
in order to admit of its shrinkage, — and then pushes the 
flap into the opening with a blunt probe. A firm binocular 
bandage is applied — but no iodoform. The eye is not 
dressed until the third day, when the anterior chamber 
is often found restored, the iris all in its proper plane, and 
the conjunctival flap healed into the ulcer. Ultimately all 
trace of the flap disappears, and an 'ordinary non-adherent 
corneal scar is presented. 

* Kuhnt's method, too, for strengthening the cicatrix, where 



CHAP. VII.] 



THE CORNEA. 



221 



an extensive ulceration with prolapse is present, by means of 
a conjunctival flap, with single or double pedicle, which is 
drawn over the ulcer, is a valuable one. If the ulcer and 
prolapse be at a (fig. 113), an incision b c is made through the 
conjunctiva along the margin of the cornea, and an incision 
d e more peripherally. The flap so outlined is dissected up, 
drawn over the cornea, ulcer, and prolapse of iris, and then 
secured to its new position by means of a suture (Fig. 114). 
In a few days the flap becomes adherent to the ulcer and pro- 




lapse, and its upper and lower positions can thus be released 
with the scissors. By this means a stronger covering for 
the ulcer and prolapse is provided, and the dangers of late 
infection and of staphyloma are minimised. 

Different types of corneal ulcers are recognised and 
described. Of these the following are the chief :— 

Simple Ulcer.— This may result from a slight trauma, 
or it may originate in a phlyctenula. It presents the 
appearance of a minute and shallow depression with a grey 
floor on the surface of the cornea. There is circumcorueal 
vascularity, especially at that part of the corneal margin 
nearest to which the ulcer is situated ; the pupil is apt to be 



222 



DISEASES OF THE EYE. 



[chap. vii. 



contracted, although iritis is not present, and there is often 
a good deal of pain, lacrimation, and photophobia. 

Treatment and Prognosis. — The eye is to be bandaged, 
warm fomentations applied several times a day, and a drop 
of solution of atropine instilled night and morning. When 
of phlyctenular origin, stimulation with the yellow oxide 
ointment is indicated. Dionine may be used. Cure, with 
slight opacity remaining, comes about in a week or ten 
days. But, if it become infected, this form of ulcer may 
pass over to the deep ulcer. 

Deep Ulcer. — This is a septic or infected ulcer, and com- 
mences in a septic infiltration of the cornea. It forms a 
tolerably deep pit in the cornea towards its centre, the floor 
of the ulcer being covered with purulent deposit and detritus, 
and the corneal tissue immediately surrounding it being some- 
what infiltrated with pus. The ulcer is generally round, but 
it may assume any shape. Hypopyon is often present, and 
a marked tendency to iritis exists. The pain is usually 
very severe, violent frontal neuralgia being a common 
symptom. 

This ulcer has no great tendency to spread over the 
surface of the cornea, but has a very decided tendency 
to perforate through it. As it does not generally attain 
wide dimensions, the perforation it may produce is small, 
and gives rise to a small adherent leucoma rather than 
to a staphyloma. It seldom causes complete loss of the eye. 

Causes. — This form of ulcer is a frequent one in gonorrheal 
ophthalmia and in blennorrhoea neonatorum ; and it may be 
caused by the lodgment of foreign bodies, and other injuries 
of the cornea. 

Treatment. — If the ulcer be due to a conjunctival process, 
the latter should be actively treated, and the only attention 
needed for the ulcer is to anticipate with paracentesis a 
spontaneous perforation. 

If the cause be other than conjunctival, a pressure 



CHAP. VII.] 



THE CORNEA. 



223 



bandage to give support to the ulcer is important, and 
periodical warm fomentations are most beneficial ; but where 
the cause is conjunctival (purulent conjunctivitis), neither 
a bandage nor warm fomentations can be used. Atropine 
should be instilled in all cases several times daily, and 
antiseptic applications, especially xeroform, are useful. 

Paracentesis of the anterior chamber through the floor of 
the ulcer is a proceeding always followed by improvement 
in the condition of the eye, and is very important as a 
preventive of natural perforation. The actual cautery, too, 
is in its place here, except when the ulcer is clue to 
purulent conjunctivitis. 

* Fistula of the Cornea. — The deep ulcer when it perforates 
is the most common cause of fistula of the cornea. A fistula 
is liable to form when the perforating ulcer is in the 
pupillary area of the cornea, so that it cannot be closed 
by the prolapse of iris into it. The opening closes then by 
the slow growth of connective tissue from its margins, and 
sometimes this process does not go on to completion, and then 
a small central fistula is left. Or, the perforation takes place 
so that just a small tag of the pupillary margin of the iris 
is incarcerated in the cicatrix, and the pulling of the iris on 
this as the pupil dilates prevents complete closure of the 
orifice. Or, if the perforation be of wide area, with exten- 
sive iris-prolapse, the pressure of aqueous humour may cause 
a small rupture in the prolapse which may not heal again. 
Through the fistula aqueous humour constantly trickles 
away, the anterior chamber remains very shallow or quite 
empty, the globe is soft, and gradually becomes softer ; or, 
the fistula closes for a time, the eye then becoming of 
glaucomatous hardness, and the high tension ruptures the 
cicatrix, which again closes, and is again ruptured by high 
tension. Finally, sight is lost through detachment of the 
retina, or through severe uveitis or haemorrhage. 

Fistula of the cornea is very difficult of cure. The 



224 



[CHAT. VII. 



treatment consists in the use of a myotic to keep the intra- 
ocular tension low. With the same object an iridectomy 
is indicated, but is difficult of performance owing to the 
shallow anterior chamber. The margins of the fistula may 
be curetted, or cut away, or cauterised, but the close 
proximity of the lens must be borne in mind, lest its 
capsule be injured by these proceedings. The anterior sur- 
face of the opening may be curetted, and a conjunctival 
flap with pedicle transplanted over the opening (p. 221) ; the 
flap healing to the curetted margin aids in the closure 
of the fistula. Or, into the opening, the margins of which 
have been previously curetted, a small flap of conjunctiva 
without pedicle may be pushed, which, healing with it, closes 
the opening. 

Serpiginous Ulcer (Ulcus Serpens, Saeruisch's Ulcer). 
This, also, is a purulent ulcer, a characteristic of which is its 
tendency to creep over the surface of the cornea, especially 
in some one direction, rather than to strike deep into its 
tissue. Its position is chiefly central, and it presents a greyish 
floor, which is more intensely opaque at some places. One 
part of the margin takes the form of a curve, or of several 
closely placed curves, and at this place the margin becomes 
yellowish-white in colour and somewhat raised, and the 
floor of the ulcer seems deeper in its neighbourhood. 
Immediately around the ulcer the cornea is slightly opaque, 
but farther out it is normal. 

The degree of pain and irritation varies much, being 
almost absent in some cases, while in others it is intense. 
Iritis is apt to come on at an early period, and may 
pass into irido-cyclitis. Hypopyon is almost always present, 
and on the posterior surface of the cornea, from the 
region corresponding to the ulcer on the anterior surface, 
a line of pus is sometimes seen extending down to the 
hypopyon, and this was formerly token as a proof that 
the hypopyon was formed by direct transmission of the pus 



CHAP. VII.] 



THE CORNEA. 



225 



corpuscles through the cornea from the ulcer. The ulcer 
creeps over the surface of the cornea in the direction of the 
curved and intensely infiltrated margin. At a still later 
stage the whole cornea is apt to become infiltrated, and 
the entire margin of the ulcer to extend, and the anterior 
chamber becomes quite full of pus. Perforation now takes 
place, or may do so somewhat earlier. If the perforation 
be small, an adherent leucoma results ; but if large, a 
staphyloma gradually develops, or panophthalmitis may 
immediately follow on the perforation. 

Causes. — Ulcus Serpens always has its origin in a trauma, 
which has produced, it may be, only a slight abrasion of the 
epithelium. In perhaps 50 per cent, of the cases chronic 
dacryocystitis is present, and in about 25 per cent, more 
there is ozcena, and a considerable proportion of them occur 
in the warm summer months. 

In most instances the pneumococcus — the usual micro- 
organism of chronic dacryocystitis — is the excitant of the 
typical ulcus serpens, but occasionally cases have been 
observed in which the pneumococcus was not present, and the 
diplobacillus liquefaciens, the streptococcus, the bacillus 
subtilis, or some rarer form of micro-organism, was held 
to be the excitant. 

J'ri/f/nosis. — From the description given, it will be seen 
that the process is a severe one in very many cases, and 
the prognosis for vision, or it may even be for retention of 
the eyeball, very serious. Yet cases of a mild type do 
occur which soon give way to ordinary routine treatment, 
and leave only a relatively small and not very opaque, 
but centrally situated, corneal cicatrix, allowing of some 
EUefal vision, which may be improved by an optical 
iridectomy. 

Treatment. — If the case be not severe, atropine, with pro- 
tection of the eye, may cure in a few days. Warm fomen- 
tations should not be used, as they rather promote the 

15 



226 



DISEASES OF THE EYE. 



[chap. vii. 



activity of the diseased process ; and the eye should not be 
bandaged, lest infective discharge be retained in the con- 
junctival sac. Antiseptic measures should always be em- 
ployed, xeroform being the application most likely to 
prove of use. It may be employed either in the form of 
a strong ointment (gr. xxx ad ^j) put into the eye, or it 
may be insufflated on the floor of the ulcer with a powder- 
blower. The floor of the ulcer may be washed with a 
solution of sublimate 1 in 5000, or other antiseptic solutions 
which do not act as caustics, the action of which on the 
healthy surrounding tissues might be difficult to control. 
Scraping the floor of the ulcer with a sharp spoon is a 
useful procedure. 

But it is in all respects wiser to deal with these cases, 
even the apparently mild ones, actively in the very com- 
mencement. If, as is so often the case, chronic dacryocystitis 
be present the lacrimal sac should at once be extirpated 
(vide chap. ix.). At the same time one or other of the 
following local measures should be employed — the second 
being the one now most in use. 

1. Samiisch's Method consists in division of the ulcer with 
a Grrefe's cataract knife. Cocaine having been applied, the 
point of the instrument is entered about 2 mm. from the 
margin of the ulcer in the healthy corneal tissue, and, having 
been passed through the anterior chamber behind the ulcer, 
the counter-puncture is made in the healthy cornea some 
2 mm. from the opposite margin of the ulcer. The edge of 
the knife being then turned forwards, the section is slowly 
completed. The incision should divide the intensely infiltrated 
part of the margin in halves. The aqueous humour and 
hypopyon are evacuated, atropine is instilled, a bandage is 
applied, and the patient soon gets relief from pain. Every 
day, until healing of the ulcer is well established, the wound 
must be opened up from end to end with the point of a fine 
probe or spatula, the contents of the anterior chamber being 



CHAP. VII.] 



THE COR-XEA. 



227 



thoroughly evacuated on each occasion, and atropine instilled. 
The result is that, in a vast majority of cases, the progress 
of the ulcer is arrested, and healing soon sets in. The little 
operation should not be delayed long ; yet it may be employed 
with advantage even in late stages of the process. A satis- 
factory explanation of its curative action has not yet been 
given. 

2. The Actual Cautery at a red heat is a very valuable 
method of treatment for this ulcer. The infiltrated and 
undermined margin of the ulcer is the part which should 
be most thoroughly cauterised ; but its floor, if much in- 
filtrated, is also to be dealt with. The application of 
fluorescin just before the use of the cautery is of much 
value, as it enables the operator to clearly discern the whole 
of the diseased part requiring cauterisation. These ulcers 
demand prompt and active treatment, before the time is 
passed when treatment can be of any practical use ; and 
the cautery undoubtedly affords the best prospect of aid of 
that kind. Even the cautery is often ineffectual to arrest 
the progress of the ulceration. 

At the thinnest part of the floor of an extensive serpiginous 
ulcer it is desirable to make a perforation through the 
cornea with the point of the cautery ; or, when the cauteri- 
sation is finished, the cornea may be paracentesed with a 
broad needle in a sound region beyond the ulcer. The ob- 
ject is to reduce the intraocular tension, and thus promote 
the nutrition of the cornea. 

Subconjunctival injections of a 4 per cent, saline solution 
are found to assist the cure (p. 218). 

Veiy recently Romer has proposed, and both he and 
some others have carried out, treatment of the serpiginous 
ulcer with his anti-pneumococcus serum. For the present it 
is unnecessary to do more than to mention this method, 
which is still on its trial. 

"Diplobacillus Ulcer.— Tliis ulcer, which is not very 



228 



DISEASES OF THE EYE. 



[chap. vir. 



common, bears some clinical resemblance to the ulcus serpens, 
and may be mistaken for it ; but it is less destructive, 
slower in its progress, and more amenable to treatment. 
Catarrhal conjunctivitis (p. 137) is usually co-existent, while 
dacryocystitis is absent, and the history of a trauma is 
commonly to be obtained. The definite diagnosis can only 
be made by means of a bacteriological examination of the 
secretion taken from the floor of the ulcer. In the initial 
stage, a central, or almost central, grey infiltration, often 
of very small size, appears near the surface of the cornea, 
surrounded by a delicate halo of less intense infiltration, 
and there is marked pericorneal injection. After a few 
days, the ulcer becomes developed. It is 2 to 4 mm. wide, 
shallow, and covered with a greyish membranous exudation, 
which can be lifted off. Occasionally the floor is greyish- 
yellow, and deep. The margin is often slightly raised, and 
sometimes undermined. The superficial layers of the cornea 
around the ulcer are somewhat ojDaque, with stippling of 
the epithelium overlying them ; and, deeper in the cornea, 
radiating grey striae reach into the healthy cornea, often 
nearly to its margin. Iritis and hypopyon are usually pre- 
sent. The severity of the corneal process in the later stages 
often alters the character of the conjunctivitis, so that 
it can no longer be recognised as catarrhal. Occasionally 
small outstanding infiltrations form in the cornea. The 
ulcer increases in size by extending all round its own 
margin, although in some cases this process, as in ulcus 
serpens, is mainly in some one direction. A neglected 
case may lead on to destruction of the eye through 
panophthalmitis. 

Treatment. — Atropine. Solution of sulphate of zinc one 
per cent, as eye drops three times a day, or direct touching 
of the ulcer with a cotton-wool pencil soaked in the solution, 
or irrigation with a small syringe. In rare cases the 
galvano-cautery may be needed. 



CHAP. VII.] 



THE CORNEA, 



229 



*Rodent Ulcer (Mooren's Ulcer). — This is a rare and 
extremely dangerous form of ulcer of the cornea, and must 
not be confounded with the serpiginous ulcer. It is not 
a purulent ulcer. The disease commences as a small — some- 
times even pinhead-sized — grey infiltration near the corneal 
margin, not differing in appearance from many a harmless 
catarrhal infiltration. This rapidly ulcerates. Other similar 
infiltrations appear in the neighbourhood and at other parts 
of the margin, and ulcerate, and the ulcers coalesce into 
one, of which the advancing margin nearest the centre of the 
cornea is undermined. The undermined margin under which 
a fine probe can be inserted, consists of partially necrosed 
corneal tissue, and presents the appearances of a narrow 
whitish line overhanging the line of active disease. The 
cornea beyond the margin of the ulcer is normal. There 
is very great pain and photophobia in some cases, and 
in others hardly any. The eyeball is injected. The ulcer 
does not go deeper than about one-fourth of the thickness 
of the cornea, and perforation seldom occurs. Occasionally 
a very small hypopyon is present, and occasionally too there 
is iritis. Before long the ulcer in its oldest portion begins to 
be vascularised and to heal, and finally leaves an intense 
cicatrix behind. Gradually the idceration creeps round the 
cornea, and at the same time advances towards its centre, by 
small infiltrations appearing just inside the opaque margin, 
and which coalesce and soon break down, while healing is 
taking place in the oldest portions of the ulcer. This process 
goes on until, finally, the whole surface of the cornea has 
been eaten away, and cicatricial tissue substituted for it, its 
centre being the last place affected, and then vision will 
have become reduced to finger-counting or to perception of 
light. The progress of the disease is very slow, many weeks 
or even some months often elapsing before the surface of 
the whole cornea has been destroyed, and the ulceration 
may become stationary for a time, only to start afresh 



230 



DISEASES OF THE EYE. 



[CHAP. VII. 



without any apparent reason. Some clearing up of the 
corneal opacity may subsequently take place, but cannot 
be reckoned upon. Yet in a few cases fairly good vision 
has been regained. The disease attacks both eyes in about 
one-fourth of the cases, although there may be an interval 
between the onset in each, of weeks, or months, or more. 
It attacks decrepit people of over middle life, but occurs 
also in young persons and in those of apparently robust 
health. Its etiology is obscure. No specific micro-organism 
has as yet been discovered as the immediate cause. 

The onset at the edge of the cornea in the form of small 
grey infiltrations, the grey and shallow floor of the ulcer, its 
pale grey or almost white margin, the undermining of 
this margin (which may readily be ascertained by passing 
the point of a probe under it), and the steady advance 
of the ulceration towards the centre and around the edge of 
the cornea, are the characteristics of this disease. 

Treatment. — Rodent ulcer is usually a most intractable 
disease, and leads to serious loss of vision. The general 
nutrition of the individual is to be improved, but reliance 
is mainly to be placed on local treatment, which should 
especially be directed to the undermined margin, or rather 
to the surface immediately underlying this, after the over- 
hanging lip has been cut away with fine sharp scissors. 
The galvano-cautery is much in use here, and it is important 
that the burning should be rather deep. Pure liquid 
carbolic acid applied with a fine bit of wood, the excess 
being taken up with a bit of blotting paper, is also useful. 
In a case under the care of one of us (li.R.S.) absolute 
alcohol applied to the ulcer (see p. 238) produced a remarkable 
and rapid cure, so that a small central area of sound cornea 
was preserved ; and a second case has been similarly cured. 
Scraping, tincture of iodine applied with a camel's-hair 
pencil, sublimate lotion, with a bandage and the usual 
warm fomentations, may help iu the treatment. The 



CHAP. VII.] 



THE CORXEA. 



231 



covering of the diseased part — after it has been well 
cauterised — or of the entire cornea, with a conjunctival flap, 
is a measure which may be worth the trial. 

^Marginal Ring" Ulcer is a rare form, which commences 
as a clean-cut, or but slightly infiltrated, yet rather deep, 
ulcer at the corneal margin. Its tendency is to extend 
along the margin of the cornea ; and in some instances 
healing takes place in the older parts of the ulcer, while it 
is still progressive at the newer parts. It may extend all 
round the cornea, and finally give rise to complete sloughing 
of the latter by cutting off its nutrition. This ulcer may 
result in children from a marginal phlyctenular infiltration 
(p. 200), but is more common in adults, or in aged people, 
whose nutrition has fallen very low. 

Treatment. — The actual cautery. Paracentesis through 
the ulcer, eserine having been first instilled. Insufflation of 
xeroform. Warm fomentations. A bandage. Quinine, iron, 
and strychnine internally, with nutritious diet. 

Absorption Ulcer (Facetted Ulcer, Superficial Transparent 
Ulcer) is the term applied to a certain definite superficial 
ulceration which is accompanied by but little opacity and by 
no vascularisation, and which is usually seated at or near the 
centre of the cornea, where it presents the appearance of a 
shallow pit about 2 mm. broad, with rounded margin, its floor 
being covered with epithelium. If the eye be exposed 
to cold, wind, or other irritation, some circumcorneal in- 
jection makes its appearance, and there is lacrimation ; 
but these symptoms soon pass off again. The healing 
process may take months to be completed, and slight 
opacity remains. Often the defect is never quite filled 
up, but a small facet is left, which is liable to interfere 
with vision. 

The absorption ulcer does not tend to perforate, nor to 
spread over the surface of the cornea. 

It occurs chiefly in childhood, and probably indicates mal- 



232 



DISEASES OF THE EYE. 



[CHAP. VII. 



nutrition of the general system ; some observers, indeed, 
think there is a close relationship between it and phlyc- 
tenular ophthalmia. It is also seen in granular ophthalmia, 
with and without pannus. 

Treatment consists in ah-opine, dionine, and protection, 
with a bandage in the early stages ; and the yellow oxide 
ointment in the later stages. General treatment with suit- 
able tonics is indicated. 

*Neuro-Paralytic Keratitis.— In paralysis of the 

Ophthalmic Division of the Fifth Nerve purulent infiltration 
with hypopyon and ulceration of the cornea is occasionally 
observed, or the process may be very superficial and aseptic. 
It was formerly believed that the fifth nerve had an 
influence over the nutrition of the cornea, and hence that 
neuro-paralytic keratitis is a trophic process ; but it has 
been shown that this is not the case, and that the affection 
is due to the diminished reflex lid-action and secretion of 
tears, and consequent drying and disorganisation of the 
corneal epithelium, which renders it possible even for septic 
infection of the cornea to take place. This disease, therefore, 
cannot be regarded as of neuropathic origin, in the strict sense 
of the term. 

That keratitis is not very common with paralysis of the 
fifth nerve, is no doubt due to the moisture of the surface of 
the cornea being sufficiently maintained through the con- 
sensual action of the eyelids of the affected eye witli those 
of the opposite eye ; and, also, that reflex lacriination of the 
affected eye, although in diminished degree, results from stimu- 
lation of the opposite cornea. Yet under certain conditions 
— e.g., if the nictitation be incomplete (partial paralysis of the 
facial nerve), or if there be some proptosis — the cornea may 
become dry, and keratitis may appear. In all the cases 
published of paralysis of each fifth nerve, keratitis appeared, 
for here the protection of the reflexes originating on the 
other side was not present. The absence of any ill-result 



CHAP. VII.] 



THE CORNEA. 



233 



to the cornea from the operation of extirpation of the 
gasserian ganglion on one side for severe neuralgia is ex- 
plained by what has just been stated. 

Treatment consists, in the milder cases, in protection of the 
cornea by keeping the eyelids closed with a bandage, or by 
fastening them together with a dermic suture. The severer 
cases of purulent infiltration or ulceration must, in addition, 
be dealt with on the lines laid down in previous pages for 
the treatment of those conditions. 

*Keratomalacia (Infantile Ulceration of the Cornea, 

with Xerosis of the Conjunctiva) is a very rare affec- 
tion. It attacks some poorly nourished children early in 
the first year of life, making its appearance at or near the 
centre of the cornea. Iritis always supervenes in severe 
cases. That portion of the bulbar conjunctiva which is exposed 
in the palpebral aperture at either side of the cornea undergoes 
slight epithelial xerosis, similar to that in functional night 
blindness, due to retinal exhaustion (see chap. xix.). Some- 
times the xerosis of the conjunctiva is absent. Ulceration 
of the cornea soon comes on, through necrosis of the layers 
lying over an interstitial infiltration ; and this ulceration 
spreads until it involves the whole of the cornea, except a 
very narrow margin. Finally, perforation, with prolapse 
of the iris, and panophthalmitis may supervene. 

Both eyes become affected as a rule, although the disease 
usually attacks one eye some time before its fellow. The 
patients almost always die of diarrhoea, pneumonia, etc. 

Cause. — Streptococci have been found in the corneal ulcer 
and in the conjunctiva, while a general streptococcus invasion 
of the vascular system of the whole body is also present. 
To the latter circumstance are referred the conditions which 
lead to a fatal termination. Many of the infants attacked 
Bare Syphilitic, but whether, as is held by some, the corneal 
process is a specific one, and not merely part of the general 
cachexia, is nn open <piestion. 



234 DISEASES OF THE EYE. [chap. vh. 



Treatment is of little avail ; but warm fomentations and 
the use of non-irritating antiseptic lotions, etc., are indicated, 
along with an antiseptic dressing. Such means as may possibly 
promote improvement of the general system are obviously 
called for. In cases of congenital syphilis, calomel internally 
is stated to have been of great service, not only to the general 
state, but also to the corneal disease. 

*Herpes Comese Febrilis. — Not only in herpes zoster 
ophthalmicus (see chap, viii.), but also in herpes febrilis (or 
catarrhalis) is a vesicular eruption liable to occur on the 
cornea. It is met with in any of the inflammatory affections 
of the respiratory tract, from a common cold, to severe 
pneumonia. Also with whooping cough, and with inter- 
mittent and typhoid fever. It can also occur as a primary 
affection. It may be of more common occurrence than 
ophthalmic practice would lead us to think, for it is the 
resulting ulceration which more commonly comes under our 
notice. The patient complains of the sensation of a foreign 
body in the eye, with lacrimation and photophobia, and these 
symptoms disappear when the vesicles burst. 

On the surface of the cornea of one eye is formed a group 
of clear vesicles, each from 0 - 5 to 1*0 mm. in diameter. They 
usually form in a line, which runs obliquely across the cornea, 
or sometimes in a vertical direction. Now and then they 
are arranged in trefoil shape or in a circle. The covering 
of the vesicles is short-lived, and, as already remarked, the 
resulting ulcer is that which the surgeon usually first sees. 
Even it, however, is thoroughly characteristic. On the sui-- 
face of the clear cornea is an irregular loss of epithelium, 
along the margins of which may still sometimes be seen the 
shreds of the late covering of the vesicle. The margin of 
the region which is bared of its epithelium is dentated, and 
can only be mistaken for a traumatic loss of epithelium. 
But the latter would not present the peculiar ' string-of- 
beads ' appearance. The floor of the loss of substance is 



CHAP. VII. J 



THE CORNEA. 



235 



formed by the superficial layers of the cornea, and anaesthesia 
of the cornea is confined to this place, and does not, as in 
herpes zoster, extend to the rest of the cornea. The tension 
of the eye is generally reduced. Under favourable circum- 
stances this loss of epithelium may be rapidly repaired; 
although even then more slowly than one of equal dimensions, 
but of traumatic origin. Usually the healing process is 
slow. Sometimes more or less intense opacities form in 
the area and at the margin of the ulcer, with hypopyon, 
iritis, etc., and the loss of substance becomes deep, with a 
dentated margin. This more unfavourable course is the 
result of secondary infection of the ulcer. 

Treatment at an early stage, before the vesicles have burst 
or the loss of substance has become infiltrated, consists in 
protection of the eye, and, when infiltration has set in, in 
disinfection, with protection. In obstinate cases 4 per cent, 
saline subconjunctival injections are often of use. If the 
vesicles give great pain they may be ruptured by dusting a 
little calomel into the eye, or by brushing it with a camel's- 
hair pencil wet with solution of boric acid, after which a 
well-fitting antiseptic dressing is applied. Cocaine should 
be used as sparingly as possible, owing to its ill-effect on 
the epithelium when used in excess. Atropine and warm 
fomentations are indicated, and a weak yellow oxide oint- 
ment is of use in some cases. Where the nostrils are 
affected, weak sublimate or other antiseptic washes should 
be applied to the Schneiderian mucous membrane. 

'Filamentary Keratitis (Fadchen-Keratitis). — This is 
very rare. Its name is due to the fine threads, like 
twisted spun-glass, several of which hang from the surface 
of the cornea, and give the condition its characteristic ap- 
pearance. These threads never reach a length of more than 
3 or 4 mm., and are composed of twisted proliferating 
epithelial cells, each ending in a bulbous enlargement caused 
by degeneration of the epithelium. The condition may 



DISEASES OF THE EYE. 



[chap. to. 



result from a superficial trauma of the cornea, or from a 
bullous or herpetic keratitis. 

Treatment. — The instillation of a 3 per cent, solution of 
chloride of ammonium into the eye every two hours, by 
which the exfoliation of the epithelial growth is promoted 
and hastened, produces a rapid cure. Protection of the eye 
with a bandage is important. 

*Bull0US Keratitis.— Bullae very rarely form on the 
cornea. They are seldom the primary condition, but usually 
depend on a diseased process in the true cornea. This process 
may itself be a primary disease ; but more commonly it, too, 
is secondary to deep changes in the eye, such as absolute 
glaucoma, iridocyclitis, etc. Very rarely bullae are seen on 
the cornea of an otherwise sound eye, in a person whose 
health is in a debilitated state. Bullae on the cornea are 
sometimes caused by blows on the eye, or by direct traumata 
of the cornea. The formation of a bulla is attended by 
much pain and photophobia, which disappear as soon as the 
bulla ruptures. One, or more than one, bulla may form at 
a time. After a day or two they rupture, and their walls 
then hang in shreds from the surface of the cornea, and 
may produce the appearance of filamentary keratitis, and 
the seats of the bullae present shallow depressions. These 
losses of substance heal without leaving any permanent 
opacity. After an interval of days or weeks another crop 
of bullae appears, and runs the same course. 

Treatment. — The bullae should be opened, and their walls 
snipped away with a scissors, and a bandage applied. The 
recurrent attacks may cease after a length of time ; but so 
far as treatment can influence them it can only be effected by 
relieving the process in the cornea which gives rise to them. 
If it be a primary process, warm fomentations, atropine, and 
a bandage, with remedies directed to the correction of any 
fault in the general state of the health which may exist, .ire 
suitable ; or if, as is more common, a deep ocular process 



CHAP. VII.] 



THE CORJSEA. 



237 



(glaucoma, etc.) be the cause, the recognised treatment for 
this latter must be adopted. 

*Dendriform (SevSpov, a tree) Keratitis. — This is a rare 
affection. It is a very superficial and chronic ulceration, 
with but little infiltration of its margins or floor, and presents 
the appearance of a fine groove, or grooves, on the cornea. 
It spreads chiefly over the central region of the cornea by 
throwing out branches on either side, while on the end 
of each branch there is usually a minute grey infiltration, 
and its true nature may easily be overlooked tinless the 
cornea be examined by the combined focal method. The 




Fig. 115. 

pain and irritation are sometimes severe, and again but 
slight or quite wanting. Some slight permanent opacity 
may remain when cure has been effected. 

Fig. 115 represents three of the most common appearances 
presented by this disease. At a in the left-hand drawing 
there is a nebula where healing has set in, while in another 
part of the same cornea the process is in an active stage. 
In the central drawing, near the upper corneal margin, 
there is a fine herpetic-like eruption, and a long groove 
passing down from it. And, in the right-hand drawing, 
the tendency to branch is well shown. 

In cases which have been long neglected, and in which 
the disease has run riot over the cornea, no healing process 



238 



DISEASES OF THE EYE. 



[chap. vii. 



having been set up, the surface becomes dull grey and 
irregular, as though ploughed up, the primary characteristic 
appearances being lost by reason of the amount of disease 
present The ulceration rarely becomes septic. 

The Cause has not been definitely ascertained, but the 
peculiar habit of the affection renders it almost certain that 
it is produced by a mould. The opinion is strongly held 
by some, that these ulcers result from a herpetic eruption 
on the cornea. 

Treatment. — Scraping with a sharp spoon, with the subse- 
quent application of 1 in 1000 solution of corrosive sublimate 
to the cornea, is recommended by some, also the application of 
pure carbolic acid to the ulcer with a fine camel's-hair pencil, 
care being taken to confine it to the ulcer, and the actual 
cautery is sometimes useful. 

It was in the fourth edition (1892) of this handbook that 
attention was first directed to the value of the local applica- 
tion of absolute alcohol in this obstinate disease, and since 
then it has proved in our hands an almost certain, as well as 
a rapid, cure in nearly every case. A small bit of lint is 
folded to a point, and the latter is dipped in the alcohol. 
The ulcerated portion of the cornea is then rubbed with the 
point with such pressure as to take away the epithelium, and, 
so far as possible, the rest of the corneal surface is avoided. 
Or, if a very little cotton wool be rolled round the end of 
a small fine bit of match wood, and this used instead of 
the lint, the application may be more accurately confined 
to the affected part of the cornea. Immediately afterwards 
the conjunctival sac is freely washed out with sterilised salt 
solution, to remove all surplus alcohol which would increase 
the subsequent pain. The application is painful even with 
cocaine. As a rule there is much pain for some hours after- 
wards, and for this hot fomentations afford the best relief ; 
cocaine is of little use. Usually one application is sufficient 
to produce cure, but some cases require it to be repeated 



CHAP. VII.] 



THE CORXEA. 



239 



after four or five days. It is not desirable to repeat 
the application more than once, or at most twice, as the 
corneal epithelium is then liable to become deranged, and 
filamentary and bullous keratitis may be produced. 

The application of a fine point of sulphate of copper 
to the ulceration also produces some good cures. It is 
less painful than the alcohol, because its action is easily 
confined to the ulcerated part, but it does not produce so 
certain a cure. 

* Keratitis Aspergillina. — This rare disease was de- 
scribed by Leber. The appearance presented is that of 
an ulcer from 3 to 5 mm. in diameter, occupying a 
rather central position in the cornea. The surface of the 
ulcer is of a pale greyish yellow, and is very irregular. 
A striking and characteristic appearance is the dryness of 
this surface, the copious discharge of tears flowing over it 
without seeming to wet it. The rest of the cornea is 
slightly opacpie and dull, and there is a small hypopyon 
present. The conjunctiva is injected and swollen, and is 
covered with some mucous secretion. The eyelids are 
rather swollen. There is photophobia and often severe pain. 
Masses removed from the surface of the ulcer and examined 
with the microscope are found to be full of the aspergillus 
fumigatus. It may usually be ascertained that an injury has 
preceded the appearance of the ulcer. 

Trejitjii'iut. — The membranous mass which forms the floor 
of the ulcer should be peeled off, and the underlying surface 
cauterised and dressed with xeroform, after which a good and 
rapid cure takes place. 

* Tubercular Ulceration of the Cornea. See p. 250. 
(b) Non-U loekative Inflammations of the Cornea. 

* Abscess. — This affection is on the borderland between the 
ulcerative and non-ulcerative inflammations of the cornea ; 
for in one case it results in an ulcer — usually the ulcus 



240 



DISEASES OF THE EYE. 



[CIIAP. VII. 



serpens — while again it runs its course without ulceration. 
The abscesses which are seated in the more superficial layers 
are those which go on to ulceration ; those in the deeper 
layers are less likely to do so. 

Abscess differs from infiltration in that the pus which 
forms it destroys the true corneal tissue— the fibrills and 
fixed corpuscles — and does not merely lie between them. 

Signs and Symptoms. — The appearance presented is that of 
a yellowish circumscribed opacity, more intense at its margin 
than at its centre, seated at or near the middle of the 
cornea, and surrounded by a light grey zone. It is usually 
round in shape, but when situated near the edge of the 
cornea it is apt to be crescentic. The surface of the cornea 
just over the abscess is at first a little elevated over the 
general surface, but later on becomes flattened, owing to a 
falling-in of the normal layers anterior to the abscess ; and 
the epithelium of the flattened part has a dull, breathed-on 
look. The rest of the cornea may also lose its brilliancy, 
although in a much less degree. Hypopyon and iritis are 
constant attendants upon corneal abscess. There is much 
injection of the conjunctival and ciliary blood-vessels. Severe 
pain in and about the eye and blepharospasm are common, 
yet occasionally a corneal abscess will be attended by but 
little pain or other irritation. 

Progress. — The abscess spreads through the cornea, usually 
in some one direction, and this direction is indicated by the 
yellowish opacity being more intense at the advancing side 
of the abscess. Before long, if the abscess be superficial, the 
layers of cornea covering it come away, and the condition is 
changed into that of the ulcus serpens already described. 
The deeper abscesses spread through the cornea more or 
less widely, and ultimately become absorbed, without having 
caused ulceration. But even these abscesses leave consider- 
able opacity behind. The process which ends in ulceration is 
the more common of the two. 



CHAP. VII.] 



'THE CO&NEA> 



24l 



Etiology. — Abscess is the result of infection of the cornea 
with pyogenic organisms, which reach it either from without, 
through some traumatic loss of substance of the corneal 
epithelium, or from within, by the agency of the blood. The 
micro-organisms, which are introduced through a superficial 
loss of substance, may either have been on the foreign 
body which produced the injury, or they may have been 
present in the conjunctival sac, or in the lacrimal sac. 
Infection through the blood is occasionally seen in some 
acute exanthematous diseases, such as scarlatina, measles, 
and smallpox ; more especially in the latter in its convalescent 
stage. 

Treatment. — Atropine, warm fomentations, and a bandage. 
But if these mild measures do not in a day or so arrest the 
progress of the abscess, resort must be had to the actual 
cautery. 

* Ring" Abscess. — This term is hardly correct, as the so- 
called ring abscess is in fact a purulent infiltration of the 
tissue of the margin of the whole cornea, or it may lie 
1 mm. or 1*5 mm., inside the actual margin. It is not a 
common affection, and is almost always caused by perforating 
wounds, including operation wounds, at any part of the 
cornea, and sometimes follows on perforating wounds of the 
sclerotic. It may also occur after spontaneous perforation 
of a corneal ulcer, the infection of an old incarcerated iris pro- 
lapse, or in metastatic ophthalmitis. Its progress is extremely 
rapid, leading on to complete necrosis of the cornea and to 
panophthalmitis within a few days after the perforating in- 
jury is sustained, and often rendering excision or evisceration 
necessary almost as soon as the case comes under observation. 
In rare instances the process is less violent, and it may 
then Ixs possible, by means of the cautery and careful 
dressing, to save some sight, or at least the shape of the 
eyeball. 

Syphilitic Diseases of the Cornea. Diffuse Interstitial 

16 



242 



DISEASES OF THE EYE. 



,[chap..vii. 



or Parenchymatous Keratitis.— This is by far the most 
common, and best known, of the syphilitic affections of the 
cornea. It is most frequently met with between the ages 
of five and fifteen. It usually commences at some one part 
of the margin as a light greyish opacity, accompanied 
by slight injection of the ciliary vessels. The rest of the 
corneal margin soon becomes similarly affected ; and then 
the opacity gradually extends concentrically into the cornea, 
or does so by sending in processes which afterwards become 
confluent. In this way the whole cornea becomes affected by 
degrees ; and its epithelium acquires the breathed-on or 
ground-glass appearance, which is seen, also, in acute glaucoma. 
Occasionally the opacity commences at the centre, and not 
at the margin of the cornea, as small grey spots, and 
extends towards the margin, which it often does not reach 
before clearing commences. 

The opacity lies in the deep layers of the true cornea, 
and is slightly more intense in spots here and there. It is 
sometimes only a very light cloud, while again the cornea 
may be so opaque as to render the iris quite invisible. 
Along with the opacity, vessels form in the cornea in its 
posterior layers, but the degree of vascularisation varies 
very much in different cases. In some the presence of 
vessels can only be ascertained by careful examination with 
a high convex glass (+ 16-0) behind the ophtha>moscope, or 
with the corneal microscope ; while in others the new vessels 
are present in great numbers, and can be readily seen with 
the naked eye. In other cases, again, close leashes of vessels 
follow the tongues of opacity into the cornea, giving rise to 
the appearance known as the ' salmon patch.' The infinite 
variety in the degree of opacity and in the amount and 
arrangement of the vascularisation, results in great variation 
in the appearances in different cases. 

When the whole cornea has become opaque, it begins to clear 
up at the margin, and the central portion becomes even more 



CHAP. VII.] 



THE CO J! XL' A. 



243 



opaque than the margin had ever been — a fact which shows 
that the very cells which entered the cornea at its margin 
have advanced to its centre. The clear margin gradually 
increases in width, until only a rather intense central opacity 
is left. This central opacity slowly breaks up, and becomes 
absorbed, but not always completely ; and then considerable 
and permanent impairment of vision may remain. Even in 
the more peripheral portions of the cornea, in some cases, 
a faint maculated cloudiness may be found ou careful ex- 
amination, years after the active process has ceased. 

In severe cases iritis and chorioiditis are nearly always 
present, although the latter is not observable until the cornea 
has become clear enough to admit of an ophthalmoscopic 
examination. The disease, indeed, must be regarded, strictly 
speaking, as one of the uveal tract, to which the posterior 
layers of the cornea, which are mainly diseased, belong. 

The two forms above described, one commencing at the 
margin, the other at the centre of the cornea, and more or 
less vascularised, but for the most part ultimately occupying 
the entire cornea, are those we are wont to find in children 
and young adults, and which, as will just now be stated, 
have congenital syphilis as their usual cause. But in older 
persons, up to thirty or thirty-five, milder forms of in- 
terstitial keratitis are met with. These rarely occupy more 
than a small region of the cornea, generally towards its 
centre, either as a patch or as a ring of opacity, and with 
little or no vascularisation. 

The affection is often accompanied by a good deal of pain 
and blepharospasm, especially in the severe vascular forms, 
and there, too, the tension of the eye is apt to be temporarily 
reduced. 

The acute stage of the disease lasts from six to eight 
Weeks, or longer. But the entire process may not be completed 
for many months, and in one case at the Victoria Hospital 
the opacity did not begin to clear away for eleven months 



21 I 



DISEASES OF THE EYE. 



[chap. vii. 



after the cornea was first attacked, the whole process ex- 
tending over a period of two years. 

In children both eyes invariably become affected, although 
not always at the same time, the onset in the second eye 
beginning often when the inflammation in the first has made 
some progress, or, perhaps, when the first eye has undergone 
cure. It is important, in the very commencement of treat- 
ment, to acquaint the patient or his parents with the likeli- 
hood of this course of events. 

In adults usually one eye alone is attacked, iritis is rare, 
the duration of the process is comparatively short, and 
complete clearing up is relatively frequent. 

Causes. — The affection is more common in girls than in 
boys, and most frequently appears during second dentition, 
when the upper incisors are being cut, or at puberty. It 
depends upon some serious derangement of the general 
nutrition ; and this, in about 70 per cent, of the cases, is 
inherited syphilis — a fact which was first pointed out by 
Mr. Jonathan Hutchinson. The children are often thin, 
anaemic, and of stunted growth, with flat nose, cicatrices 
at the angles of the mouth, and are often more or less deaf ; 
and the peculiarities of the incisor teeth, so well known from 
Mr. Hutchinson's description, are present in about one-half 
of the cases. 

Occurring in adults, the affection is rarely due to inherited 
syphilis, although acquired lues may sometimes be taken as 
its cause ; while, again, it will often be impossible to assign 
any origin for it other than the universal one of exposure 
to cold, etc. Some cases are due to tubercular disease 
(see p. 250). 

Prognosis. — In children — in view of the possibility of an 
incomplete clearing of the cornea, as well as of the serious 
uveal conqjlications liable to supervene, and which may com- 
pletely annihilate vision — the prognosis must be guarded, 
although by no means hopeless, in those cases where the 



CHAP. VII.] 



THE CORNEA. 



245 



opacity is very intense, or where there is much vascularity. 
Yet in the milder cases a favourable prognosis may be given. 
The affection does very rarely recur. 

In adults, as stated, the prognosis is much more favourable. 

Treatment. — In the early stages no irritants should bo 
locally applied. Atropine is important for the prevention of 
iritis or of posterior synechia? ; and the use of radiant heat, 
in the form of hot poultices or fomentations, or the Japanese 
warmer, promotes the nutrition of the cornea and hastens 
the cure by absorption of the cellular elements which form 
the opacity. Dionine is often very useful. A bandage 
should be worn. Subconjunctival injections of the oxycyanide 
of mercury 1 in 5,000, are often useful. When the acute 
stage is ended, the yellow oxide ointment may be employed 
with benefit for stimulating the absorbents to carry off what 
remains of the opacity. Massage may be used with advantage 
in both stages to disperse the infiltration. In severe cases 
a course of mercurial inunctions, continued for several 
weeks, is very advisable ; care being taken not to allow 
stomatitis to exceed moderate bounds. In mild eases a tonic 
plan of treatment, with iodide of iron and cod-liver oil, is 
the most suitable. 

Counter-irritation, in the form of blisters to the temple or 
a seton in the scalp, is extensively employed by some surgeons. 
We do not use this treatment, as we doubt its value, and 
are loth to add to the worries inseparable from so wearisome 
a disease. 

The following much rarer forms of syphilitic disease of the 
cornea are described : — 

* Specific Punctiform Interstitial Keratitis. — Circumscribed, 
pinhead-sized, greyish infiltrations form at various levels in 
the otherwise clear stroma of the true cornea. They do not 
grow larger, nor suppurate. They form rapidly, and disappear 
rapidly when cure commences, leaving little or no opacity 
behind. The affection is not associated with iritis, but there 



246 



DISEASES OF Till': EYE. 



[chai>. vi r. 



is usually some ciliary injection. In somewhat similar cases 
the punctiform opacities are not so defined but are surrounded 
by a halo of lighter opacity, and iritis is present. This 
affection is a manifestation of tertiary syphilis, and the 
punctiform opacities have been regarded as the products 
of a gummatous inflammation. The ti'eatment would be 
iodide of potash internally, and locally atropine, warm 
fomentations, and a bandage. 

* Gumma of the Cornea. — Some cases of true gumma of the 
cornea have been recorded. The growth appears as a pale 
grey or whitish elevation, more or less vascularised, on the 
cornea. The diagnosis depends very much on the patient 
being the subject of tertiary syphilis. The treatment is 
iodide of potash. 

* Keratomalacia is also reckoned by some to be a syphilitic 
affection (see p. 233). 

* Keratitis Profunda. — This presents the appearance 
of a greyish opacity in the deep layers of the cornea at 
or near its centre, which gradually increases in intensity and 
extent, but never reaches the margin of the cornea. The 
epithelium of the cornea over the infiltration is dull and 
stippled. There is but little vascularisation, and no great 
tendency to inflammation of the uveal tract. After some 
weeks the infiltration gradually breaks up and becomes 
absorbed, leaving in severe cases a good deal of opacity, and 
in less severe cases a fairly clear cornea. The affection is 
seen only in adults, and its etiology is unknown, but 
rheumatism, malaria, and traumatism have been held ac- 
countable for it. It seems probable that it is the result of 
a localised derangement of the posterior epithelium of the 
cornea ; but if that be so, the ultimate cause of that de- 
rangement has not yet been suggested. 

Treatment. — Atropine, warm fomentations, dionine, sub- 
conjunctival saline injections, and bandage, with care of the 
general health. 



CHAP, vn.] 



THE CORXEA. 



247 



* Guttate or Nodular Keratitis, and Grating-like or 

Reticular Keratitis. — These were originally described 
as separate diseases by separate observers, but it is now 
recognised that they are essentially one and the same disease, 
and that merely an unimportant difference in the form of 
the appeai-ances presented by the cases exists. This nodular 
or reticular keratitis — a satisfactory title is wanting — is a 
rare disease. Its presence is apt to be overlooked in the 
early stages; for by focal illumination th'e cornea may seem 
perfectly normal, and the rest of the eye, except perhaps 
for some slight distension of the anterior ciliary and larger 
conjunctival vessels, is healthy, and the eye is free from 
irritation. The patient merely complains of slight burning 



Fig. 116. — Nodular Keratitis. Mr. W. J. Hancock's case. Trs. O.S. xxv. 

sensations, especially during use for near work, of some 
photophobia, and of somewhat diminished acuteness of vision. 
Transmitted light from the mirror displays in the illu- 
minated pupillary area of the cornea a number of small 
opaque patches of all shapes, occupying the most central 
position, while between them, and sometimes reaching out 
more towards the periphery of the cornea, but often leaving 
a clear zone inside its margin, innumerable very fine dots 
are present — nodular keratitis. In some cases the opaque 
patches are absent, while a number of fine forked lines are 
seen in the early stage outside the central region, which at 
first is occupied by fine dots alone. At a later period, the 
arrangement of the radiating forked lines assumes a some- 
what reticulated appearance, like that of a grating, and they 




218 



DISEASES OF TnE EYE. 



[chap. vii. 



extend to the centre of the cornea — reticular or grating- 
like keratitis (gitterige keratitis). The corneal microscope 
shows that these dots, patches, and lines are greyish, and 
situated close under the epithelium. The surface of the 
latter is, in the early period, in no way altered. Gradually 
the diseased appearances increase in amount, the anterior 
ciliary vessels become more distended, vision sinks lower, 
and the patient may sometimes complain of slight pain, 
with lacrimination, and swelling of the eyelids ; but more 
commonly there is no irritation. The lines, dots, and 
patches now begin to show slight elevations on the cornea, 
although covered by epithelium. At a still later period the 
opacity in the centre of the cornea becomes more intense, 
a marginal zone of the cornea remaining fairly clear. At 
this stage the diagnosis may again become doubtful, owing 
to the amount of the disease which obscures the characteristic 
appearance. Both eyes are always affected, either simul- 
taneously, or with a short interval. The disease is ex- 
ceedingly intractable and chronic, lasting many years, and 
finally causing much loss of sight. Most of the cases 
observed have been in young adult males, and it often 
attacks more than one member of a family, in one or in 
succeeding generations — it is, in fact, one of the family 
diseases. No relation to syphilis or other constitutional 
disease has been made out, although Wehrli has raised a 
strong suspicion that it is a tubercular malady, and even 
calls it lupus of the cornea. 

Treatment. — Treatment, so far, has proved of little, if any, 
benefit. Yellow oxide of mercury ointment, warm fomenta- 
tions, galvanism, and hydrate of chloral eye-drops have been 
used. The more modern methods with dionine and sub- 
conjunctival injections should also be given a trial. And, 
if the disease is to be regarded as tubercular, treatment with 
tuberculin T.R. is indicated. 

* Discoid, or Annular, Keratitis (Keratitis Disciforniis, 



CHAP. VII.] 



THE OOENM I. 



249 



Fuchs). — This disease occurs for the most part in persons 
of middle age, and frequently commences with slight defects 
of the epithelium caused by traumata or by herpes. It 
has also been seen by Schirmer in connection with vaccine 
vesicles on the eyelids or conjunctiva. It is characterised by 
a delicate grey disc which is situated deeply in the true 
cornea, at or near its central region, and which is marked 
off sharply all round from the normal peripheral portion of 
the cornea by a more intensely narrow grey margin or ring ; 
or, outside this ring, there may be another or even two more 
peripheral rings, all concentric with each other. With the 
corneal microscope grey stria? can sometimes be seen in the 




Fig. 117.— Forms of Discoid Keratitis (After Schirmer). 

opacity, which may radiate out into the clear cornea, 
parallel with each other or crossing at various angles, 
similar to those which occur in some other keratitides. 
The surface of the affected region is dull and its sensation 
diminished. In the course of the malady, which may run 
over several months, slight superficial ulcerations occur, and 
finally a rather intense opacity is left at the seat of the 
disease. The uveal tract is not usually implicated, but in 
rare instances the presence of some punctate deposits may 
be detected. 

Treatment is of little avail. It should consist in atropine, 
bandage, hot fomentations, subconjunctival saline injections, 
and dionine. 

* Tubercular Keratitis.— Tubercular disease of the 
cornea presents itself in several forms : — 



250 



DISEASES OF TEE ATA'. 



[chap. VII. 



1. Pale yellow nodules which appear at the corneal 
margin, extend to its deep, but not to its deepest, layers, and 
protrude slightly over its surface, accompanied by ciliary 
injection. These nodules advance towards the centre of 
the cornea, become confluent, and finally undergo absorption, 
leaving an intense opacity behind ; or they may break down 
into ulceration, which may occupy most of the corneal 
surface. The ulcer never perforates, and after a time healing 
takes place with cicatricial opacity, which may clear up to a 
great extent. This is the only truly primary form of 
tubercular disease of the cornea, no other part of the eye 
being affected, and it is rare. In the other forms of tuber- 
cular corneal disease the process is propagated to it from 
neighbouring parts. 

2. Diffuse interstitial (or parenchymatous) keratitis. In 
about 70 per cent, of the cases of this affection congenital 
syphilis is recognised as its cause (p. 244). It is now held 
that of the 30 per cent, which remains most, if not all, of the 
cases depend on tubercle, but without the presence in the 
cornea of tubercular nodules. Tubercular disease of the 
anterior uveal tract (see chap, xi.), co-exists ; and, presumably, 
the corneal affection is the effect of toxines diffused in the 
cornea from the angle of the anterior chamber. This form 
is capable of complete retrocession. 

3. Greyish sclerotising opacities caused by tubercular 
nodules, which grow into the corneal margin in its deepest 
layers from the ligamentum pectinatum. These opacities 
occur at several parts of the periphery of the cornea ; and, 
by throwing forward tongues, they slowly spread into the 
cornea. Although the process may cease at any point, the 
cornea remains very opaque at the parts attacked, with 
resulting disfigurement or loss of sight. 

4. Miliary tubercular nodules may form in the cornea in 
connection with tubercular episcleritis at the corresponding 
portion of the corneal margin, and may spread further into 



CHAP. VII.] 



TEE COBNE L. 



251 



the cornea. These nodules do not ulcerate, and ultimately 
disappear leaving opacity behind. 

5. Pannus, ulcers, and granulations, as the result of 
tubercle of the conjunctiva. The ulcers sometimes perforate. 
In the scrapings from tubercular ulcers the tubercle bacillus 
may be found. 

Treatment. — For tubercular ulceration, curetting, with the 
insufflation of xeroform, or, should these fail, the cautery. 
For the other forms tuberculin T. R. is indicated (see 
chap. xi.). Guaiacol and creosote have been vised internally. 

* Keratitis Punctata. — Until recent years this term was 
only given to a condition which occurs in cyclitis, in irido- 
cyclitis, and in sympathetic ophthalmitis, and which is not 
a primary disease of the cornea, and therefore does not 
come within the scope of this chapter. It will be considered 
under those headings (chap, x.) ; and it need only here be 
stated that it consists in the deposit, in the form of fine dots 
on the back of the cornea, of lymph derived from inflamed 
portions of the uveal tract, mainly from the inflamed ciliary 
processes. For it the term punctate deposits is to be pre- 
ferred to keratitis punctata. 

Fuchs has described a form of keratitis which he terms 
Keratitis punctata superficialis, and which has a good claim 
to that name. It begins with the symptoms of an acute 
conjunctivitis, but there is decided pericorneal injection, 
while the conjunctiva is not much injected, nor is the discharge 
mucous or purulent, but is rather an abundant lacrimal secre- 
tion. There is photophobia and pain. Either at the same 
time, or some days or weeks afterwards, minute grey spots 
may be seen in the superficial layers of the cornea, the 
epithelium over the spots being somewhat raised up, giving 
a dull appearance to the corneal surface. The spots are 
often arranged in groups or rows, and may be scattered over 
nearly the entire cornea, or else confined to its central region. 
There may be but a few of them, or there may be a hundred 



252 



DISEASES OF TJTE E ) E. 



[chap. vii. 



or more, and one or both eyes may be affected. The initial 
irritative symptoms soon disappear ; but the spots themselves 
remain for many weeks, or longer, and finally fade away com- 
pletely. The disease is more common in young people than in 
later life, and occurs usually in connection with a catarrh of 
the air passages ; but it must not, by reason of this, be 
confounded with herpes of the cornea. One or both eyes 
may be attacked. The spots are often very faint, and hence 
can easily be overlooked, unless searched for with the com- 
bined focal method. In this country the affection is rather 
rare, but several cases of it have come under our notice. 

The Treatment should consist in atropine, bandage, and 
warm fomentations. 

* Sclerotisillg Opacity of the cornea sometimes compli- 
cates scleritis, affecting the margin of the cornea in the 
neighbourhood of the scleral affection, but not extending more 
than 2 to 3 mm. into the cornea, except in very severe cases. 
It is an intense white opacity situated in the true cornea, 
and is apt to remain as a permanent opacity, even when 
the scleritis undergoes cure. In such cases of sclero-keratitis 
iritis is often present. 

Treatment. — Atropine, warm fomentations, massage, sub- 
conjunctival saline injections, and the treatment of whatever 
constitutional derangement of health (rheumatism, syphilis) 
may be held to have given rise to the scleritis. 

Ribandlike Keratitis (Transverse Calcareous Film of 
the Cornea ; Calcareous Film of the Cornea). — This is a 
degenerative alteration which occurs chiefly in the cornea? of 
eyes destroyed by severe intraocular processes, such as 
iridocyclitis, sympathetic ophthalmitis, glaucoma, etc. 

It also occasionally occurs as a primary disease in some 
persons of advanced life. In these latter instances glaucoma 
often comes on at a later period, or the corneal disease 
may be followed by iridocyclitis, or central chorioiditis. 
It seems probable that, in these primary cases, the cause of 



chap, vn.] THE CORNEA. 



the degeneration is simply a loss of vital energy in the 
corneal tissue, due, it may be, to vascular changes. 

The disease occupies that transverse strip of the cornea 
which is uncovered in the commissure of the eyelids during 
waking. It usually commences on the inner margin of the 
cornea, but soon appears at the outer margin, and advances 
from each direction towards the centre, where the two 
sections join. It presents the appearance of a greyish-brown 
opacity, with, in most cases, white calcareous deposits in 
and under the epithelium. In blind eyes which are con- 
stantly rolled upwards, the opacity is found, not in the 
central transverse section of the cornea, but in the exposed 
lower third. The opaque masses consist of carbonate and 
phosphate of lime. Leber puts forward the view that an 
abnormally abundant supply of phosphate of lime in the 
blood, and nutritive fluid of the cornea, is the cause of 
this condition, the rapid evaporation on the exposed part 
of the cornea being the reason why the deposit takes place 
there. The deposit is at first in Bowman's membrane, but 
later on it may appear in the anterior layer of the true 
cornea, and in the epithelium. 

Treatment. — Some improvement may be effected by scraping 
away the chalky deposit. 

ECTASIES OF THE CORNEA. 

Staphyloma of the Cornea is the result of a perforating 
ulcer of the cornea. In foregoing pages the methods 
for obviating, so far as possible, the occurrence of 
corneal staphyloma have been set forth. The ulcer, having 
htaled, may present a weak cicatrix, which becomes bulged 
forwards by even the normal intraocular tension (Figs. 118 
and 110). If the iris be not incarcerated in this cicatrix the 
anterior chamber will be made deeper (Fig. 119). 

Staphyloma cornea', in which the iris is incarcerated, is 




254 



DISEASES OF THE EYE. 



[chap. vii. 



probably a more common condition than the above. When a 
corneal ulcer is large, a correspondingly large portion of iris 
is liable to become prolapsed into it, and to form a bulging 
mass. This may burst and collapse, and a flat cicatrix may 
be formed ; or, if it do not rupture, it may form what is 
termed a partial staphyloma of the cornea and iris, the latter 
becoming consolidated by the formation of a layer of connective 
tissue over it. 

If the whole, or a very large part, of the cornea be destroyed 
by an ulcer, the iris is completely exposed. It soon begins 




Fig. 118 (Pagvwstecher). Fig. 119 (Pagensteeher). 

to be covered with a layer of lymph, which gradually 
becomes converted into an opaque cicatricial membrane. 
Should this not be strong, the normal intraocular tension is 
sufficient after a time to make it bulge ; or, increased intra- 
ocular tension may arise in consequence of further changes 
within the eye, and then bulging of the pseudo-cornea all 
the more surely comes on, and the condition is termed total 
staphyloma of the cornea, although obviously the term is 
somewhat strained, as in fact there is no cornea. Some- 
times a total staphyloma has a lobulated appearance, owing 
to the pseudo-cornea having some of its fibres stronger 
than others ; and hence the name given to the condition 
(from ara^vXr), a bunch of grebes), and which has in time 
become applicable to almost any bulging of the cornea or 



CHAP. VII.] 



THE COltA'EA. 



255 



sclerotic. Such stnphylomata are apt to gradually increase 
to a very large size. 

Treatment. — In cases of partial staphyloma, where a clear 
portion of the cornea remains, an iridectomy is frequently 
indicated for the reduction of the tension — so that further 
bulging may be arrested — as well as for the sake of the 
artificial pupil, which may improve sight, in cases where the 
normal pupil is obliterated by corneal opacity. 

When, sight having been lost, the staphyloma is very 




Fig. 120. 



prominent, or when total staphyloma is present, enucleation 
of the eyeball, or one of the following operative measures, 
must be adopted. 

AbscUsicm. — A Beer's cataract knife being passed through 
the base of the staphyloma, with its edge directed upwards, 
the upper two-thirds of the staphyloma are separated off, 
while the remaining third is detached by means of a scissors. 
If the lens be present it must now be removed. The wide 
opening becomes filled up with granulations, and becomes 
cicatrised. 



256 



DISEASES OF THE EYE. 



[chat. vii. 



In de Wecker's method the opening is closed with con- 
junctival sutures. The operation is commenced by separating 
the conjunctiva all round the margin of the cornea, and by 
then loosening it from the eyeball nearly as far back as the 
equator. Four sutures (a, b, c, d) of different colours are 
then passed through the conjunctiva about 2 to 3 mm. from 
the margin of the wound, as represented in Fig. 120. In 
order to keep the field of operation clear, the ends of two 
of these sutures are laid over on the nose, while the others 
are laid over on the temple. The staphyloma is now abscised, 
and the sutures drawn together and tied. 

The foregoing and other methods of abscission are only 
applicable where the tension is either low or normal. If 
it be high, the liability to intraocular haemorrhage during 
the operation makes enucleation, evisceration, or Mules' 
operation more suitable proceedings. Indeed, probably most 
surgeons would now employ one of the two latter operations 
in all these cases. 

Evisceration was proposed about the same time by Grrefe, of 
Halle, to obviate meningitis after the removal of suppurating 
globes ; and by the late Mr. Mules, of Manchester, chiefly 
to take the place of enucleation in cases of sympathetic 
ophthalmitis. Many surgeons are opposed to its employment 
in these latter cases, but for staphyloma of the cornea it 
cannot meet with any such opposition. 

The cornea is removed by making an incision with a 
Grsefe's knife, so as to include one half of the corneo-scleral 
margin, and by completing the circumcision with scissors. All 
the contents of the globe are then evacuated by means of 
Mules' scoop, care being taken to remove the chorioid 
unbroken by carefully peeling it from the sclerotic margin 
backwards, until it is only held at the lamina cribrosa. The 
scoop is then used to lift out the separated unbroken chorioid 
and the other contents of the globe. 

Finally, the margins of the sclero-coujunctival wound are 



CHAP. VII.] 



THE CORNEA. 



267 



drawn together with a few points of suture. The whole 
proceeding should be done with strict antiseptic precautions, 
chief among which is the free use of irrigation with a 1 in 
5000 solution of corrosive sublimate before, during, and 
after the operation, the interior of the globe being most 
carefully washed out with the solution in a full stream. 
The result is a fairly good and freely movable stump for 
the application of an artificial eye. 

* Mules' Operation. — This proceeding — a modification of 
the foregoing — was also proposed by Mules for cases of 
threatened sympathetic ophthalmitis, and, like simple evis- 
ceration, has not yet met with universal acceptance in those 
cases, because many fear that it does not afford sufficient 
protection against sympathetic ophthalmitis. We do not 
participate in this feeling. In cases of staphyloma, however, 
and in some other conditions where the questions of sym- 
pathetic ophthalmitis, or of a new growth in the eye to be 
operated on, do not enter into consideration, no proceeding 
is more satisfactory, at least in young persons, than this 
beautiful one of Mules'. The prothesis it gives is almost 
perfect. Its object is to provide a still better stump for 
the artificial eye by the insertion into the scleral cavity of 
a hollow glass sphere. It is performed as follows : — 

The cornea is removed — the conjunctiva having first been 
freed from the scleral edge towards the equator of the eye- 
ball — and the contents of the eyeball evacuated, as in simple 
evisceration. The opening is now enlarged vertically, to 
admit of the introduction of one of the glass spheres. This 
introduction is best effected by means of a special instrument 
designed for the purpose by Mules. The spheres are made 
in several sizes to suit different cases, and it is well not 
to use the largest which will fit into any given eye. The 
Spll ere having been inserted, the margins of the sclerotic 
opening are united vertically by some points of interrupted 
suture, for whicli purpose silk or hemp is preferable to catgut, 

17 



258 



DISEASES OF THE EYE. 



[CHAP. VII. 



as the latter is apt to undergo absorption before complete 
union has taken place. The conjunctival opening is then 
closed by another set of sutures placed at right angles to the 
sclerotic line of closure. Similar antiseptic precautions are 
required, as in simple evisceration, and all bleeding should 
have ceased in the cavity before the glass sphere is inserted. 
Before the lids are closed the anterior surface of the globe 
is well covered with boric acid or xeroform. A firm antiseptic 
bandage is applied. The eye is not dressed for forty-eight 
hours, and subsequently once every twenty-four hours, using 
the sublimate solution freely. There is generally some 
reaction, consisting of chemosis, swelling of the eyelids, and 
pain, and sometimes these symptoms are very marked, 
especially if too large a sphere have been employed. In the 
course of a week or so this all passes off, and a very perfect 
stump is obtained. 

The danger that the glass sphere may be broken by a blow 
upon the eye has been put forward as an objection to this 
method. No doubt it is an accident which may occur, and 
would then necessitate the enucleation of the eye ; but no 
case of the kind has as yet been recorded, although the opera- 
tion has been in use for more than twenty years. Silver 
spheres, instead of those of glass, have been sometimes 
employed to obviate the danger referred to. 

We recommend this procedure, and use it frequently. 
With a well-fitting glass eye, the cosmetic result it gives is 
infinitely better than that produced either by complete enu- 
cleation or by evisceration of the eyeball. It is more 
uniformly successful in young people than at more advanced 
ages, and therefore it is better not to use it in persons over 
twenty-five. To ensure success it is an important point 
that the glas.i globe be not too large — it should be an easy 
fit for the cavity of the sclerotic. In case the* sutures give 
way, and the sclerotic opening gapes, an attempt -may be 
made to reclose it with new sutures, but this is not often 



CHAP. VII.] 



THE CORNEA. 



259 



successful. As a rule the glass globe must in that event 
be removed, and the case then becomes one of simple 
evisceration. 

* Frost's Operation. — Mr. Adams Frost, with the object of 
securing the safety of complete excision, with the cosmetic 
advantages of Mules' operation in cases of intraocular 
growth, and in cases in which sympathetic ophthalmitis is 
feared, has suggested the following proceeding. 

The eyeball is excised in the usual manner. Immediately 
the globe has been removed, firm pressure is made for a 
minute or two with a pledget of wool to arrest all bleeding. 
A Mules' sphere is then inserted into the capsule of Tenon, 
and the conjunctiva is instantly brought together and held 
over the sphere with forceps, while the sutures are intro- 
duced. Three sutures are generally sufficient, and care 
must be taken to insert them sufficiently far back to avoid 
any risk of their cutting out. In performing the operation 
the chief point is to lose no time in introducing and fixing 
the sphere, otherwise blood becomes extra vasa ted into the 
tissues, the introduction of the sphere is rendered difficult, 
and it is liable subsequently to escape. In the earlier 
operations Mr. Frost picked up and sutured the muscles, 
but he found that time was thus lost, while there was no 
compensating advantage. If the operation is performed in 
the manner described, the muscles attach themselves to the 
covering tissue and a very movable stump results. The 
sutures may be left in a week, and the dressing and after- 
treatment are the same as for Mules' operation. Oc- 
casionally the conjunctiva fails to unite over part of the 
wound, the opening then usually enlarges, and the sphere 
escapes. If this should occur, the tissues fall together and 
the conditions are then the same as after an ordinary 
excision, and more favourable, Mr. Frost thinks, than after 
an unsuccessful Mules', in which, in his experience, the 
schra often slowly sloughs away. Attempts to close an 



260 



DISEASES OF THE EYE, 



[CHAP. VII. 



opening exposing the sphere have not in Mr. Frost's hands 
been successful. He finds that, if the tissues unite over the 
sphere, they do not often subsequently give way, although 
no doubt this happens more frequently than after a Mules'. 
* Conical Cornea, or Keratoconus.— In this condition 

the cornea is altered in shape to that of a cone, as 




represented in Fig. 121. If the apex 
be touched with a probe its extreme 
thinness may be ascertained. The 
cornea remains clear, except some- 
times just at the apex of the cone, 



Fig. 121. where a slight nebula may be present. 

The position of the apex of the cone 
is usually not quite central, and is then most commonly 
either in the lower outer, or lower inner, quadrant of the 
pupil. The condition is easy of diagnosis in its advanced 
stages by mere inspection of the cornea, especially in profile, 
but in its commencement it may not be so readily detected. 

In the early stages, when the light is thrown on the 
cornea from the ophthalmoscope mirror, the corneal reflex will 
be noticed to be smaller at the centre, owing to the greater 
curvature there, and a dark shadow, circular or crescentic in 
shape according to the incidence of the light, appears between 
the corneal margin and the corneal centre. When the 
fundus is examined its details will be seen distorted. 

In some extreme cases, the patient observes a pulsating 
alteration in the size of the objects looked at. This is due 
to the pulsation of the apex of the cone, imparted to it by 
the intraocular circulation, and comparable to the pulsation 
of an unclosed fontanelle of the skull. Objectively the pulsa- 
tion can be seen with the corneal microscope. 

On examining the cornea with the keratoscope 1 

1 The keratoscope is a disc made up of concentric black and white 
circles. These circles are not equidistant, but their radii are calculated 
according to the law of tangents, so that, when reflected on a normal 
spherical cornea, they appear in the image to be equidistant. 



CHAP. VII.] 



THE CORNEA. 



261 



(Placedo's disc) the corneal reflex, instead of being normal, 
as at A (Fig. 122), is altered as at B or C. 

With the astigmometer, the portions of the images on the 
apex are smaller and overlap, while the more peripheral 
portions may only touch, or may even not come into contact. 

The process begins in early adult life, progresses slowly, 
never leads to rupture or ulceration of the cornea, and, 
finally, after many years, ceases to progress, but does not 
undergo cure. Both eyes are apt to become attacked, one 
after the other. The disturbance of vision is very great, 
owing to the extreme irregular astigmatism produced. 

The change is due to a gradual and slowly advancing 




ABC 



fig. 122. — A, Reflected image on normal cornea. B, Reflected image 
at apex of cone in conical cornea. C, Reflected image slightly 
eccentric in conical cornea. 

atrophic process in the cornea, at or near its centre, in con- 
sequence of which the normal intraocular tension acts on 
it so as to distort it into the conical form. The patho- 
genesis of the condition is not clearly understood. By 
some it is held to be due to congenital weakness at the 
centre of the cornea, as the result of mal-development, 
while others explain it by a chronic degeneration of the 
membrane of Descemet. 

Treatment. — In the early stages, or in slight cases, an 
improvement in vision may be obtained by means of concave 
spherical or sphero-cylindrical glasses ; for, as is evident, 
the change in shape of the cornea must cause the eye to 
become myopic. The refraction of the central portion of the 
cornea may be ascertained by retinoscopy^ with the aid of 



2fi2 



DISEASES OF THE EYE. 



[chap. vii. 



a stenopeic disc in the trial frame. At a later period these 
glasses are of little use. Hyperbolic lenses have been em- 
ployed, but, although they may raise the acuteness of vision, 
there are obvious difficulties in the way of the practical every- 
day use of them. A stenopeic slit renders assistance in 
some cases, especially in reading. 

A few cases are reported in which the keratoconus was 
much reduced and vision greatly bettered by instillations of 
eserine, and the application of a pressure bandage, continued 
for several months. 

But it is upon operative measures, with the object of 
flattening the cornea, that we must chiefly rely for auv 
practically useful improvement in sight. 

Von Griefe's Method consists in the production of an ulcer 
on the apex of the cone,' and the resulting cicatricial con- 
traction. From the surface of the cornea, a little to one 
side of the apex of the cone, a morsel of corneal substance 
is removed with a cataract knife, care being taken not to 
open the anterior chamber. On the second day after this 
proceeding the wound is touched with mitigated lapis (solid), 
and this is repeated every third day for a fortnight or three 
weeks. Paracentesis of the anterior chamber is then per- 
formed through the floor of the ulcer, and the aqueous 
humour is evacuated every second day for a week, after 
which the healing process is allowed to take its course. A 
bandage must be worn during the whole course of the treat- 
ment. Finally, when the contraction and consequent flat- 
tening are completed, a narrow optical iridectomy may be 
necessary, in consequence of the central, or almost central, 
and rather intense corneal opacity. 

Sir William Bowman's Method consists in cutting a disc 
on the apex of the cornea, but not through its whole thickness, 
with a small trephine, and in then dissecting off this disc 
with forceps and cataract knife. Cicatrisation of the wound 
produces the desired flattening of the cone. 



CHAP. VII.] 



THE CORNEA. 



263 



Mr. Stanford Morton employs a modification of an operation 
described by Mr. Higgens. He excises an elliptical piece from 
the apex of the cone by transfixing it from above downwards, 
about midway between its base and apex, with a long narrow 
rigid Graefe's knife, of which the edge is directed forwards 
and inclined slightly to the right. The knife is pushed 
onwards until it cuts its way out a little to the right of 
the apex of the cone, the aqueous escaping at the same time. 
The flap thus formed is then lifted up well by a fine 
forceps, and the knife — with its edge now turned to the left 
— is passed beneath the points of the forceps, and by cutting 
forwards the flap is excised. The sides of the wound should 
be steep and incline towards each other at an angle of 30° 
to 45°. The apex of the cone being usually somewhat down- 
wards and inwards, or outwards, from the centre of the 
cornea, it is important, in order to prevent an anterior 
synechia, to avoid carrying the incision too far downwards. 
The eye should be well soaked with atropine, both before 
and after the operation, and a firm compress kept on for 
some time after the wound has healed. 

Multiple puncturings of the apex of the cone with a fine 
cataract needle have been employed. The summit of the 
cone is transfixed from three to six times at each sitting, and 
this may be repeated at intervals of two weeks or more. The 
first effect of the punctures is to allow some of the aqueous 
humour to escape, and then the eye is firmly supported with 
a bandage. The pupil is kept under the influence of eserine. 
Eventually a network of cicatricial tissue forms, which flattens 
the cone without giving rise to much corneal opacity. 

A satisfactory proceeding, .and the one now most commonly 
adopted, is the application of the electro or thermo-cautery 
at a red heat to the apex of the cone. By this means a 
contracting cicatrix is produced, which brings about a general 
flattening of the cornea, while the operation is practically 
free from risk. The cauterisation must be strictly confined 



261 



DISEASES OF THE EYE. 



[chap. vii. 



to a small area at the apex of the cone, and the cornea 
should not be perforated with the cautery. The operation 
may be repeated over the same area at intervals of ten to 
fourteen days, to bring about a more intense cicatrix. 

Sir A. Critchett lays much stress on the graduated applica- 
tion of the cautery. He first applies the cautery at a black 
heat to the whole area intended to be cicatrised ; within 
this area a little more is destroyed at a slightly increased 
heat, while the very apex is touched with a cautery at a dull 
red heat. One sitting is sufficient. 

After the cicatrisation following on cauterisation is com- 
pleted, the scar is to be tattooed, and an optical iridectomy 
will usually be required, especially if the cone has beeu 
quite central. The cases in which the apex of the cone 
has an eccentric position are those most benefited by 
cauterisation, because the resulting scar interferes less with 
vision than where it is central. 

Tumours of the Cornea. 

* Primary tumours of the cornea are extremely rare. Epi- 
thelioma and sarcoma have their origin not in the cornea, 
but in the limbus conjunctivae (p. 196). Dermoid tumours 
are usually seated partly on the conjunctiva and partly on 
the cornea (p. 193). Yet a very few cases of papilloma, 
epithelioma, and fibroma are recorded as taking their origin 
in the cornea. Corneal cysts also occur. 

Injuries of the Cornea. 

Foreign Bodies in the Cornea, such as morsels of iron, 
stone, coal, etc., are amongst the most common of all accidents 
to the body. The pain caused by these foreign bodies is 
very considerable, as can be understood, when the rich nerve- 
supply of the surface of the cornea is considered. 



CHAP. VII.] 



THE COILXEA. 



265 



The dangers which may follow on the presence of a 
foreign body in the cornea depend partly upon the infec- 
tion or non-infection of the foreign body, and partly upon 
the depth at which it is buried in the cornea. The deeper 
a foreign body lies the more difficult will be its removal, and 
the greater must be the laceration of the cornea caused by 
that proceeding. A foreign body which carries infection will 
be more likely to set up serious inflammatory reaction than 
one which is aseptic or nearly so. For this reason it is im- 
portant to ascertain, if pos- 
sible, the origin of the 
foreign body, although an 
apparently aseptic origin 
must cot set all fear on 
this point at rest. Atoms 
of hot metal are from their 
temperature aseptic. 

Many foreign bodies are 
so small as to defy detection, 
until the cornea is searched 
with the oblique illumina- 
tion — an aid which should 
always be made use of, when 
the symptoms or history in the remotest way suggest the 
presence of a foreign body. 

A foreign body which lies quite superficially in the 
epithelium is easily removed by gentle wiping with a clean 
camel's-hair pencil, or soft cloth. Those which lie deeper 
require instrumental interference, in the following manner : — 

The eye having been thoroughly cocainised, the patient is 
seated, and leans his head against the chest of the surgeon, 
who stands behind him (Fig. 123). With the index-finger 
of the left hand the surgeon then lifts the upper lid of the 
injured eye, pressing the margin of the lid upwards and 
backwards, while with (ho second finger he depresses the 




266 



DISEASES OF THE EYE. 



[chap. vii. 



lower lid in a similar manner. By this means the eyelids 
are held open, and also, to a great extent, the motions of 
the eyeball are controlled. The foreign body is now to be 
pricked out of the cornea with a special needle, with as 
little injury of the general surface as possible, the patient 
all the while directing his gaze steadily at some given 
point. If the foreign body be deep in the layers of the 
cornea, it must be dug out, as it were ; and a minute gouge 
is made for this purpose. In the case of a morsel of iron 
or steel which has lain for some time in the cornea, a small 
ring of rust will be seen surrounding the late seat of the 
foreign body after its removal. This rust-ring is in the true 
cornea, and must be carefully scratched away, or the recovery, 
by necrosis of the affected part, will be much slower, and the 
resulting opacity much greater. 

Care must be taken not to infect the cornea in the removal 
of a foreign body, and consequently thorough aseptic pre- 
cautions, especially as regards the instrument used, must be 
taken. After the foreign body is removed, the place where 
it was seated should be washed with a 1 in 5000 solution 
of corrosive sublimate. A bandage is worn until the epithelium 
is regenerated — i.e., for a day or two. 

The maguet is of no use for the removal even of super- 
ficially seated foreign bodies of steel or iron in the cornea. 

Sometimes a foreign body in the cornea will be long enough 
to protrude somewhat into the anterior chamber, and there 
is danger that, in the attempts at removal, it may be pushed 
farther on, and fall into the anterior chamber. Here it is 
necessary to pass a keratome through the cornea, and behind 
the foreign body, so as to provide a firm base against which 
to work, or the keratome may be made to push the foreign 
body forwards. 

The wing-cases of small beetles and scales of seeds may 
get into the eye, aDd adhere to tho cornea by their concave 
surface for several days. 



CHAP. VII.] 



THE CORNEA. 



267 



Simple Losses of Substance, or Abrasions, of the 

surface of the cornea, involving the most anterior layers of 
the true cornea, or perhaps merely the epithelium, are very 
common from rubs or scratches with branches of trees, 
finger-nails, etc., etc. These injuries heal readily if the eye be 
protected with a bandage ; but, when neglected, or if septic 
matter have been introduced when the injury occurred, or if 
it be present in the conjunctiva or lacrimal sac, these losses 
of substance are capable of forming the starting-point of 
corneal abscess (p. 239), ulcus serpens (p. 224), etc. 

* A remarkable condition known as Recurrent Abrasion, 
or Disjunction of the Cornea (and also as Traumatic 
Keratalgia, and Recurrent Traumatic Keratalgia) is some- 
times observed to follow upon abrasions of the cornea. 
Healing of the primary lesion having taken place in an 
apparently normal manner, the patient, after an interval of 
days, weeks, or even months, on awaking in the morning, 
is seized with severe pain, similar to that experienced on 
the occasion of the injury. On examination of the eye a 
loss of the epithelium, which may be greater or less in 
extent than was the primary loss, is found at the seat of the 
original lesion, or, what is remarkable, it may have taken 
place elsewhere on the cornea. Or, more rarely, instead 
of a loss of epithelium, the latter may be raised up like a 
vesicle, or bulla. Examination of such cases has shown that 
the epithelial covering of a great part of, or of the whole 
of the cornea may be easily lifted off with a forceps ; in 
short, that the cohesion between epithelium and Bowman's 
membrane far beyond the immediate seat of the original 
lesion has become imperfect. Care of the eye by means 
of a bandage enables the renewed loss of substance to be 
rapidly repaired ; but, after a period of quiescence, another 
attack takes place on awaking in the morning, or in the 
cour.se of the night, and such attacks may continue to 
recur, even for several years. It is characteristic of the 



268 



DISEASES OF THE EYE. 



[CHAP. VII. 



affection that the attacks always take place on awaking a 

circumstance which is explained by the slight adhesion 
between palpebral conjunctiva and corneal epithelium formed 
during sleep, so that on the lifting of the eyelid the loosened 
epithelium is torn away, or lifted in a bulla-like shape. 
There is some loss of sensation of the surface of the cornea. 
After one of these attacks, examination of the corneal sur- 
face by the usual methods may fail to reveal the presence 
of a loss of substance, and then it may be discovered by 
means of transmitted light from a plane mirror, which will 
display the defect as a black mark. The corneal microscope, 
too, is useful here. 

The cause of disjunction of the cornea has not been 
definitely ascertained. The view has been put forward, and 
there is good evidence in support of it, that the affection is 
due to a very slight degree of oedema of the cornea of neuro- 
genic origin, a derangement of the peripheral endings of the 
fifth nerve in the cornea having been produced by the original 
injury. 

Treatment. — Cocaine, owing to the disorganising effect it 
has on the corneal epithelium, is to be used as sparingly 
as possible. A carefully applied bandage is important, and 
should be worn for long — it may be weeks — after the re- 
current lesion seems to be quite well. An operative measure 
— namely, the removal with the forceps of the entire corneal 
epithelium or as much of it as easily comes away, is very 
effectual. The denuded region is soon again covered over 
with epithelium, and this new growth adheres in a healthy 
manner to its bed. Some surgeons remove the loosened 
epithelium with a camel's-hair pencil moistened with chlorine 
water, and others take it away with a curette. The inser- 
tion into the conjunctival sac of an non-irritating ointment 
every night at bed-time is a useful adjunct in the treatment 
by bandage or operation. 

Blows On the Eye, amongst other lesions, are liable to 



CHAP. VII.] 



THE CORNEA. 



269 



cause Corneal Bulla?, the walls of which consist of Bowman's 
membrane and the epithelium. In some cases these bulla? 
contain blood, derived no doubt from the ruptured canal of 
Schlemm. Such bullae may also form after burns with 
lime, etc. 

Another condition caused by blows on the eye is Hcemor- 
rhagic Discoloration of the true cornea, which presents a 
greenish or a reddish-brown colour in the cornea. Haemor- 
rhage in the anterior chamber is always present at first. 
At first, too, the discoloration occupies the whole cornea, 
and after a time begins to clear up from the margin towards 
the centre. The prognosis for vision is good, if the eye be 
otherwise sound, but the absorption of the colouring matter 
in the cornea is excessively slow, and as much as two or 
three years or more may elapse before the process is 
complete. Mr. Treacher Collins has ascertained that the 
peculiar discoloration in these cases is due to the presence 
of haematoidin, which he thinks enters the cornea from the 
haemorrhage in the anterior chamber through Deseemet's 
membrane by a process of diffusion. He did not find any 
red blood-corpuscles in the cornea. 

Burns of the Cornea. — Burns of the cornea from lime 
are not uncommon. The lime acts as a caustic, and 
destroys the cornea more or less deeply, with resulting 
more or less intense permanent cicatricial opacity. The 
lime, moreover, enters into chemical combination with the 
corneal tissues in the form of the albuminate of lime, which 
causes further opacity. 

Treatment. — As soon as possible after lime has entered 
the eye, it should be removed as thoroughly as possible 
by means of forceps and free washing out with water ; 
or, better still, with saturated solution of sugar, which 
forms, with whatever loose lime may be present, an in- 
soluble substance that may be readily removed. 

The removal of such albuminate of lime as remains 



270 



DISEASES OF THE EYE. 



[chap. vii. 



fastened deeply in the cornea is difficult to effect. When 
the irritation of the eye has subsided, a warm 2 per cent, 
solution of chloride of annnonium, which dissolves out the 
lime, may be applied, by means of an eye-bath, to the cornea. 
The bath is to be used several times a day for half an 
hour each time, and the strength of the solution may be 
gradually increased, according as the patient can bear it, 
up to 20 per cent. 

Perforating Injuries of the Cornea. — In these cases 
the injury done is rarely to the cornea alone, and at 
the first inspection the attention of the surgeon is occupied 
less with the state of the cornea than with the question 
as to whether, and to what extent, deeper parts of the 
eye (iris, lens, vitreous humour, etc.) are involved. Another 
very important point, which has often to be decided, is 
whether or not the foreign body, which has perforated 
the cornea, is contained in the eye. But these matters 
belong to future chapters. 

A perforating wound of the cornea, which does not involve 
any other part, is serious in proportion to its extent, and 
to the probability of its being infected. Every perforating 
corneal wound is followed by loss of the aqueous humour, 
which flows away through the opening, and by consequent 
collapse of the anterior chamber ; but this in itself is not 
a serious event. Short wounds close almost at once (and 
through them indeed very little of the aqueous humour 
may flow off), the aqueous humour is rapidly restored, and 
no harm is done to the eye beyond a slight opacity, which, 
if in the pupillary area, may cause some defect of vision ; 
or, should the wound be situated more peripherally, and 
should the iris have lain against the cornea for a while, 
an anterior synechia may form. 

Long wounds, which may even occupy the cornea in its 
entire diameter without directly involving any other organ 
of the eye, are almost certain to be complicated by pro- 



CHAP. VII.] 



THE CORNEA. 



Ill 



lapse of the iris between the lips of the wound ; and, when 
healing takes place the prolapsed portion becomes per- 
manently incarcerated in the cicatrix. At the least, this 
incarceration causes irregularity in the curvature of the 
cornea, and consequent irregular astigmatism. But it may 
be the starting-point of a staphyloma of the cornea, it may 
become the cause of glaucomatous intraocular tension, or, if 
at any time a slight trauma with loss of substance of its 
surface should occur, it may take on septic inflammation, 
which may spread rapidly to the deeper uveal structures, 
leading to panophthalmitis and loss of the eye. 

Treatment. — In small uncomplicated perforating wounds, 
without prolapse of iris, the aqueous humour being still 
wanting, atropine should be freely used if the wound be 
towards the centre of the cornea, or eserine if it lie toward 
the periphery, with the object of preventing adhesions of 
the iris to the posterior aspect of the wound, and a bandage 
should be applied to the eye. 

In recent injuries of this kind, in which there is a pro- 
lapse of the iris, the prolapsed portion, if not very large, may 
sometimes be reposed with a spatula or fine probe, aided 
by the action of atropine or eserine, according to the position 
of the wound. But in many instances this attempt will 
prove futile, while in those in which there is suspicion 
of septic infection, it is unwise to make it at all. In 
either circumstance the prolapsed portion of iris should be 
snipped off at its base. It is not enough to abscise a 
portion of the summit of the prolapse. The prolapsed 
iris must be seized with an iris-forceps, drawn forward 
so as to loosen any adhesions between it and the lips of 
the wound (or the adhesions may previously be separated 
by a probe passed round the edges of the wound), and 
cut off close to the cornea. This affords the best hope 
of the iris receding into the anterior chamber without 
any of it adhering in the cornea. In badly lacerated 



272 



DISEASES OF THE EYE. 



[CHAP. VII. 



wounds it is sometimes desirable to transplant conjunctiva 
over them (p. 221) in order to promote the healing process 
and to consolidate the cicatrix. 

In cases which are not recent, the adhesions between 
cornea and prolapsed iris will have become so firm, that 
it will not be possible to separate them by any means, 
and the prolapse must be left to become cicatrised over, 
attention being directed to keep the tension of the eye 
low by means of eserine, punctures made in the prolapse, 
and the transplantation of conjunctiva, so as to produce a 
firm and flat cicatrix. 



Opacities of the Cornea. 

Nebula, Macula, Leucoma. — These terms are applied 
to opacities of varying degrees in the cornea, which are the 
result of some diseased process, or which are consequent upon 
an injury. The first term is used for very slight opacities, 
often discoverable only with oblique illumination. Macula 
indicates a more intense opacity, recognisable by daylight. 
Leucoma is a completely non-translucent and intensely white 
opacity, the result almost always of an ulcer, which has 
destroyed most of the true corneal tissue at the affected 
place ; indeed, it is often the result of an ulcer which has 
eaten its way quite through the cornea. In these latter 
cases the iris may have become adherent in the corneal 
cicatrix, and then the term adherent leucoma is employed. 

Very often eyes with an old-standing nebulous condition 
of the cornea are myopic. It is probable that this myopia 
is produced partly by the habitual close approximation of 
objects to the eye, owing to the diminished acuteness of 
vision from the opacity of the cornea. 

Treatment. — Little or nothing can be done to reduce these 
opacities. In slight and fresh cases, massage with the 



CHAP. VII.] 



THE CORNEA. 



273 



yellow oxide of mercury ointment may render them less 
intense. 

In case of a nebulous cornea, a stenopeic apparatus often 
improves the sight. This consists of a metal plate with a 
small central hole or slit, which is placed before the 
patient's eye in a spectacle-frame ; and by this arrangement a 
large portion of the rays which pass through irregular parts 
of the cornea, and which merely confuse the sight, is cut 
off. Should the opacity be dense, and situated in the centre 
of the cornea, portion of the margin having remained clear, 
an iridectomy will in some instances improve the sight. 

The Operation of Tattooing was first proposed by De Wecker, 
and is a valuable proceeding for improvement of the appear- 
ance of the eye in cases of leucoma. It is also an extremely 
useful method for improvement of the sight, where the nebula 
occupies only part of the pupillary area of the cornea. In 
these latter cases, much disturbance of sight is caused by the 
dispersion of the light which makes its way through the 
nebula ; and when, by tattooing the scar, all light is pre- 
vented from getting through, brighter and distincter vision 
is enjoyed with the part of the cornea, opposite the pupil, 
which is absolutely clear. 

In the case of a leucoma, either the whole surface of the 
leucoma may be tattooed, or only part of it — e.g., its centre, 
in order to represent a pupil. 

The material used is fine Indian ink rubbed into a very 
thin paste. The eye having been cocainised, the leucoma 
is spread over with this paste, and then covered with in- 
numerable punctures by means of de Wecker's multiple 
tattooing-needle, or with an ordinary discission needle, 
each stab of which carries into the cicatricial tissue 
some of the black pigment. Tbe coloration continues 
sufficiently intense for some months, but then often begins 
to get pale, owing, probably, to the pigment falling out 
of the punctures. A method of tattooing, by which the 

18 



274 



DISEASES OF THE EYE. 



[CHAP. VII. 



pigmentation lasts longer, is performed with de Wecker's 
single grooved needle. The pigment is placed in the groove 
of the instrument, which is then passed into the leucoma, 
a long canal being made in a plane parallel to its surface. 
On withdrawal of the needle the pigment remains behind. 
A large number of such canals must be made in close 
proximity to each other, until the desired intensity of colour 
is obtained. Some operators remove the corneal epithelium 
over the part to be tattooed, in order to facilitate the entrance 
of the colouring matter into the true cornea. 

In tattooing the cornea, the eye must not be fixed with a 
toothed forceps, or the conjunctiva may be tattooed. A 
forceps armed with rubber is made, or the eye can be fixed 
by the surgeon with his fingers, which at the same time take 
the place of a speculum (see p. 265). 

* In cases where the whole cornea is leucomatous, and, con- 
sequently, where no restoration of sight can be obtained by 
means of an artificial pupil, Transplantation of a Portion of 
Clear Cornea from a rabbit's eye, or from a freshly enucleated 
human eye, has been repeatedly performed by ophthalmolo- 
gists in various parts of the world. Very many of these 
operations have been perfectly successful in a surgical sense — 
i.e., in so far as the healing-in of the transplanted flap was 
concerned ; but, with a few exceptions, they all ended in 
disappointment, in consequence of the flap not retaining its 
transparency. In the course of a week or two the trans- 
planted portion invariably became as opaque as the leucoma 
bad been before. The mode of proceeding consisted in 
removing a portion of the leucoma with a trephine, and in 
then cutting a disc with the same instrument out of the clear 
cornea to be utilised, and inserting it into the opening in 
the leucoma. 

Various theories were put forward to account for the occur- 
rence of the opacity in the transplanted flap, but into these 
it is unnecessary to enter here. Von Hippel came to the 



CHAP. VII.] 



THE CORNEA. 



275 



conclusion tnat the onset of the opacity in the flap was due 
to entrance of the aqueous humour into the substance of 
the cornea, owing to the solution of continuity in its posterior 
epithelium ; for it has been shown that, unless this epithe- 
lial layer be intact, the toansparency of the cornea cannot 
be maintained. Von Hippel, acting on this theory, applied 
a trephine to the leucoma as deep only as the posterior elastic 
lamina, and then dissected off the superficial layers contained 
within the ring, leaving the posterior elastic lamina and 
posterior epithelium. With the same trephine he then 
excised a disc of its entire thickness from a rabbit's cornea, 
and applied it to the wound. Iodoform was dusted over this, 
and a bandage applied. Healing took place readily, and 
twenty months afterwards the flap continued transparent, 
and vision = Yon Hippel has had some other suc- 

cessful cases, but the cases to which the proceeding is applic- 
able are not of frequent occurrence. 

ArcUS Senilis.— This is a change which is developed in 
the cornea without previous inflammation. It presents the 
appearance of a greyish line all around and a little inside the 
margin of the cornea, most marked above and below, and 
never advancing farther towards its centre. It is more 
common in elderly people, but is sometimes seen in youth, 
and even in childhood. No functional changes are caused by 
it, nor does it interfere with the healing of a wound which 
may be made in that part of the cornea. Arcus senilis, 
as Mr. Parsons' investigations have shown, is caused by a 
peculiar fatty degeneration of the corneal cells and fibrillar. 



CHAPTER VIII 



DISEASES OF THE EYELIDS. 

Erythema, erysipelas, phlegmonous inflammation, and abscess 
are all liable to attack the eyelids, but require no special 
observations in this work. It should merely be stated that 
erysipelas of the eyelids may extend to the connective tissue 
of the orbit, and ultimately give rise to atrophy of the optic 
nerve. 

Eczema. — This is very often seen on the skin of the eye- 
lids, most frequently in connection either with general eczema 
of the face or with phlyctenular ophthalmia. The lacrima- 
tion in phlyctenular ophthalmia increases the eczema, which 
then, by causing contraction of the skin of the lower lid, 
often produces eversion of the inferior punctum lacrimale, 
and this, in turn, causes increased lacrimation. 

Atropine infiltration of the eyelid, from use of atropine 
eye drops in some persons, is frequently accompanied by a 
moist form of eczema of the lids and face. 

Treatment. — Should the use of atropine be the cause it is 
necessary to discontinue it, and to substitute solution of 
extract of belladonna as eye drops (gr. x and ^j)- As an 
application to the affected skin the following ointment is 
useful :— Oil of Cade, iv, Zinci oxidi, gr. v, Adipis lanae 
hyd. vaselin alb., aa. ^ij. 

Marginal Blepharitis (/3\e<j>apov, eyelid), or, Ophthalmia 

Tarsi, is nothing else than eczema of the margin of the 

eyelid. It is found either as Blepharitis Ulcerosa 

(Eczema Pustulosa), or as Blepharitis Squamosa (Eczema 



CHAP. VIII.] 



THE EYELIDS. 



277 



Squamosa). In blepharitis ulcerosa, small pustules form at the 
roots of the eyelashes, and these, having lost their covering, 
become ulcers, which scab over. The whole margin of the 
lid may then be covered with one large scab, in which the 
eyelashes are matted, and under which the lid will be found 
swollen, red, and moist, with many minute ulcers and pus- 
tules, the latter due to suppuration of the hair follicles 
and sebaceous glands belonging to them. Cicatrices resulting 
from this suppuration are also present, and there the hair 
follicles are destroyed, and the cilia do not grow again. 
Many eyelashes come away with the scab, and others are 
found loose and ready to fall out. 

The disease is chronic, and is most commonly seen in 
strumous children. It is frequently accompanied by phlyc- 
tenular ophthalmia, or by simple conjunctivitis, which may 
have been its cause, or which promotes it by keeping the 
margin of the lid constantly wet. 

If neglected, ulcerous blepharitis, by reason of the scars 
it produces, is liable to give rise not only to loss of eyelashes, 
but to irregular growth (trichiasis) of those which remain. 
After a time the continued congestion and inflammatory 
swelling of the lid margin leads to its hypertrophy. This 
change, which is called tylosis, is seen chiefly in the upper 
lid. The margin of the lower lid is liable to become everted, 
owing to cicatricial contraction. Involved in this eversion is 
the lower punctum lacrimale, and consequently lacrimation 
ensues, with resulting eczema of this skin of the eyelid, 
which in turn promotes the ectropion, while the exposure 
of the conjunctiva of the lower lid increases the already 
existing conjunctivitis. 

The Treatment of Ulcerous Blep/ucritis consists, in the first 
place, in the careful removal of the scabs without causing 
any bleeding of the delicate surface underneath. Such 
bleeding indicates that newly formed epithelium has been 
torn away, and it ia important, therefore, to soften the scabs 



278 



DISEASES OF THE EYE. 



[CHAP. VIII. 



by soaking the eyelid with olive oil, or with a warm saturated 
solution of bicarbonate of soda, before removing them. Any 
pustules found under the scab should be punctured, and all 
loose eyelashes, which act as foreign bodies, taken away, and 
the ulcers should be carefully touched twice a week with a 
fine point of solid mitigated lapis. The surface should then 
be well dried by pressure, not by rubbing, with cotton wool, 
and the following ointment rubbed in with the tip of the 
finger — Hydrarg. pracip. alb. gr. vj, Zinci oxidi gr. viii, Liq. 
plumbi subacid w\ vj, Adipis benzoat. ad. ^iv. This ointment 
is to be continued by the patient, night and morning, after 
the lids have been washed, and all scabs and loose eyelashes 
removed from them, and well dried, until healing is 
thoroughly established. In many mild cases a boric acid 
ointment (gr. v ad gj of vaselin or of lanolin) will be found 
efficacious instead of the above. A creolin ointment suits 
many cases, if it does not irritate — viz., Creolin, 1 to 5 min. ; 
Aq., 3ij \ Lanolin, $vj. 

Or, again, after the scabs and loose eyelashes have been 
removed as above, the margins of the eyelids may be freely 
bathed with a wash of ten to twenty minims of creolin to eight 
ounces of water, and after this the creolin ointment may 
be applied. A first principle of treatment in all these cases 
is that it be non-irritating. 

All complications with conjunctival affections or lacrimal 
obstruction must be attended to, and the patient's general 
system carefully improved. 

Squamous Blepharitis comes on after the ulcerous form 
has passed away ; or it is found as a primary affection, 
especially in chlorotic women. The margin of the lid is 
somewhat swollen and red, and covered with loose epidermic 
scales. It is an extremely chronic affection, but, although 
disfiguring, it has no dangerous sequelae. 

The Treatment of Squamous Blepharitis. Boric acid oint» 
ment (gr. xxx ad Sjj). 



CHAP. Till.] 



THE EYELIDS. 



279 



Chlorosis, if present, is to have suitable remedies. 

Phtheiriasis ($0elp, a louse) Ciliomm. — The pediculus 
pubis occurs on the eyelashes. It gives rise to excessive 
itching and burning sensations, and the consequent rubbing 
produces excoriations of the margin of the lid. The lice 
occupy chiefly the roots of the eyelashes, to which they 
cling tenaciously, while the shafts of the cilia are covered 
with their brown egg-capsules, and this gives to the 
cilia the peculiar appearance of being covered with dark 
brown powder, which enables the diagnosis to be easily 
made. The fully developed parasites, as well as the 
eggs, may be more readily seen by aid of a strong convex 
glass. 

Treatment. — With a cilium forceps the pediculi may be 
removed, as well as some of the eggs from the cilia. This 
proceeding repeated daily, along with the application of 
mercurial ointment, or of a weak red precipitate ointment, 
to the margin of the eyelids morning and evening, will soon 
effect a cure. 

Hordeolum (hordeum, a grain of barley), or Stye, is a 
circumscribed purulent inflammation situated at the follicle 
of an eyelash. It commences as a hard swelling, with more 
or less tumefaction and oedema of the general surface of the 
lid, and often with some chemosis, especially if it be situated 
at the outer canthus. In its early stages there is much pain 
associated with it. It gradually suppurates, and may then be 
punctured or allowed to open of itself. 

Styes frequently come in rapid succession, and then, 
probably, a constitutional disturbance exists as the cause. 
In the earliest stage cold applications may be successful in 
putting back a stye, but, later on, warm stupes will hasten 
the suppuration and relieve the pain. Habitual constipation 
is a common source of hordeolum, and should be met by the 
use of mild laxatives. .Sulphide of calcium, ^ gr. every 
hour, or \ gr. twice a day, for an adult, has been recom- 



2S0 



DISEASES OF THE EYE. 



[CHAP. VIII. 



mended as a specific in these cases, and treatment with 
nuclein may be found useful. 

Chalazion (x«Xa£a, hail), Meibomian Cyst, or Tarsal 

Cyst, is probably a granuloma in connection with a 
Meibomian gland, and not a mere retention cyst. Micro- 
organisms have been found by some observers in these 
tumours, but what relation exists between them and the 
tumours is a matter upon which opinions differ. Chalazion 
has its origin in a slight chronic inflammatory process in the 
connective tissue surrounding the gland, which usually passes 
off without having attracted the attention of the patient, 
but occasionally, when the cyst has developed, acute in- 
flammation with formation of pus comes on. The tumours 
vary in size from that of a hemp-seed to that of a hazel-nut, 
causing a marked and very hard swelling in the lid without 
any redness of the latter. They occasionally open sponta- 
neously on the conjunctival surface, giving exit to contents 
which are usually viscid or grumous, and sometimes 
purulent. 

Treatment. — No application can bring about absorption of 
these tumours. The lid should be everted, the tumour 
opened by an incision from the conjunctival surface, and 
its contents thoroughly evacuated by aid of a small 
curette. Difficulty is sometimes experienced in finding the 
point in the conjunctiva corresponding to the tumour, but 
it is usually indicated by a dusky or greyish discoloration. 
Immediately after the evacuation, bleeding into the sac often 
takes place, and causes the tumour to remain for a day or 
two as large as before — a fact of which the patient should 
be warned. The operation may occasionally require to be 
repeated. The interior of the sac should not be touched 
•with nitrate of silver ; and the incision and evacuation 
should not be made through the skin, unless in rare instances 
when the capsule is exceptionally thick, as more or less 
disfigurement from the scar results. 



CHAP. VIII.] 



THE EYELIDS. 



281 



More than one chalazion is often present at a time, and 
some people become liable to them periodically during a 
number of years, especially those who suffer from acne of 
the face. 

* Milium (milium, a millet seed) presents the appearance 
of a perfectly white tumour, not much larger than the head of 
a pin, in the skin of the eyelid. It is a retention tumour 
of a sebaceous gland, and can readily be removed by puncture 
and evacuation. 

* Molluscum, or Molluscum Contagiosum.— This is a 

white tumour in the skin of the eyelid, which may attain the 
size of a pea. At its summit is a depression, which leads 
to an opening into the tumour, through which the contents 
can be pressed out. It is probably a diseased condition of a 
sebaceous gland, and contains altered epithelial cells, and 
peculiar bodies, termed molluscum corpuscles, which are of 
a fatty nature. Many such tumours may form in the lids 
at the same time. It is held by some observers that this 
affection is contagious, although in what way is not clear, 
inasmuch as experimental rubbing of the contents of a 
molluscum into the skin has not given rise to the tumours. 

Treatment. — Each separate tumour must be evacuated by 
simple pressure, or after it has been opened up with a knife 
or scissors. 

Teleangiectic Tumours, or Naevi, of the eyelids occur 

congenitally. 

Treatment. — Small tumours of this kind may be destroyed 
by touching with nitrate of silver or hydrochloric acid, or by 
performing vaccination on them in the Infant, instead of 
on the arm. Larger tumours may be ligatured or treated 
with the galvano-cautery, or ethylate of soda, and electrolysis 
is a very effectual method in many cases. 

'Xanthelasma (%av06<;, yellow; eXaa/xa, a layer) is the 
term applied to yellowish plaques raised slightly over the 
surface of the skin of the eyelid, with very denned margins, 



282 



DISEASES OF THE EYE. 



[CHAP. VIII. 



Women are more liable to it than men. The patches are gener- 
ally bilateral and symmetrical, and are most frequently situated 
in the neighbourhood of the inner canthus. The shape of 
these plaques is extremely irregular, and they may attain 
the size of a shilling or larger. The appearance is caused, 
as Parsons has shown, by changes in the middle layers of 
the corium, consisting of aggregations of large epithelioid 
cells, with development of connective tissue, and of yellowish 
brown pigment in and about the cells, with fatty degenera- 
tion of the connective tissue. 

Treatment can only consist in removal by careful dissection, 
and this is hardly to be recommended except under exceptional 
circumstances. 

*Palpebral Chromidrosis (%pw,iia, colour ; iSpcom?, sweat- 
ing). — The phenomenon of an exudation of pigment upon 
the eyelids, of which a good many cases are recorded, has 
given rise to much discussion. The opinion held by many is 
that these cases are always the result either of deception in 
hysterical individuals, or of accidental circumstances, such as 
the exposure of a patient with seborrhcea palpebrarum to an 
atmosphere loaded with coal-dust or pigmentary matter, in 
some manufacturing district. Of the fact that the appear- 
ance has occurred under both of these conditions there can 
be no doubt. There would seem also to be evidence that 
some genuine cases of colour-sweating on the eyelids have 
been observed ; but they must be extremely rare. The dis- 
coloration is blue or black, and occurs in the form of fine 
powder upon the skin of one or both eyelids of both eyes. 
It can be wiped off, and is said to begin to reappear after a 
short interval. The subjects of it have been chiefly young 
girls, but it has also been seen in women of advanced years, 
and even in middle-aged men. 

The Treatment in a genuine case may consist in the applica- 
tion of a lotion of liq. plumbi and glycerine ; and, internally, 
iron, quinine, and arsenic, along with the regulation of 



CHAP. VIII.] 



THE EYELIDS. 



283 



the general system, particularly in respect of any uterine 
derangement. 

Herpes Zoster Ophthalmicus is a herpetic eruption of 

the skin in the region supplied by the ophthalmic division 
of the tifth nerve of one side. 

Occasionally in the same case the second division of the 
fifth nerve may be affected, and, yet more rarely, the third 
division as well. One or two cases, too, have been published 
in which the zoster affected each side of the face. 

But by far the most common case is the simple herpes 
zoster ophthalmicus, in which only the region supplied by 
the ophthalmic division of the fifth nerve is affected ; and of 
this region it is usually that portion alone which pertains 
to the supra-orbital and infra-trochlear branches that is 
involved, as is represented in Fig. 124. The number of 
vesicles varies much ; there 



may be but one, or there may 
be several, or they may be 
so numerous as to become 
confluent. 

The appearance of the erup- 
tion is often preceded by a 
feeling of general discomfort, 
gastric disturbance, and high 
temperature. Yet more com- 




monly is the eruption preceded 
by supra-orbital neuralgia, 
which is often of intense Fig. 124. 

severity. This pain usually 

continues, but may cease, after the eruption comes out, 
and sometimes it persists even for months after the erup- 
tion disappears. Photophobia, due to the irritation of the 
fifth nerve, is not uncommon at the commencement of the 
affection. Along with the appearance of the herpes the skin 
of the forehead becomes red and swollen, and the appear- 



284 



DISEASES OF THE EYE. 



[chap. ran. 



ances are often mistaken for erysipelas, but the strict 
limitation of the eruption by the middle line of the forehead 
is of itself sufficient to indicate the diagnosis. The upper 
lid is somewhat cedematous and red, and droops over the eye, 
and this is much more marked when the skin of the eyelid 
itself is the seat of vesicles. 

The contents of the . vesicles soon become purulent and 
haemorrhage may form in them. They then gradually dry 
up, nnd form crusts, which conceal more or less deep ulcers, 
and as these penetrate to the corium they leave permanent 
scars behind, which at first are red, and later become of a 
glistening white. The entire eruptive process lasts about 
three weeks ; and, when it is completed, the sensibility of 
the affected skin remains dull for a considerable time. 
Herpes zoster ophthalmicus is more common in advanced life 
than in youth, but it may appear at any age, even as early 
as the sixth month after birth. 

The disease is not associated with danger to the eye, 
unless keratitis come on, or, what is much more rare, 
unless iritis, cyclitis, or chorioiditis appear. Hutchinson 
laid down the rule that the cornea does not become affected, 
unless the eruption appear on the region (the side of the 
nose) supplied by the naso-ciliary nerve — this beiDg the nerve 
which gives the long root to the ciliary ganglion, as well 
as the long ciliary nerves — but it is a rule to which there 
are many exceptions. The conjunctiva is almost always 
slightly chemotic and injected, or there may be true con- 
junctivitis ; but vesicles are not often seen on it. 

There is considerable variety in the forms of keratitis 
liable to occur in herpes zoster ophthalmicus — viz., herpetic 
vesicles, phlyctenular, bullae (any of which may go on to 
ulceration), superficial opacity without loss of substance, and 
parenchymatous opacity, either diffuse or punctate. The 
superficial opacities without loss of substance may disappear 
completely. Parenchymatous opacity either clears away 



CHAP. VIII.] 



THE EYELIDS. 



285 



altogether, or remains as a slight nebula ; while ulceration 
leaves, at the least, some opacity ; or, if it become septic, 
may seriously endanger the eye. Anaesthesia, more or less 
well marked, attends the corneal affections, and remains for 
a long time after they recover. 

Iritis is very uncommon in herpes zoster ophthalmicus, and 
is usually of a mild type, and irido-cyclitis and chorioiditis 
are still more uncommon. They seldom occur unless keratitis 
be also present, and, like the keratitis, for the most part only 
when the cilio-nasal nerve is implicated. 

Herpes zoster ophthalmicus is due to an inflammatory 
process in the Gasserian ganglion, as Head and Campbell have 
shown, and in the opinion of these authors the skin eruption 
is caused by intense irritation of the ganglion cells. The 
lesion in the Gasserian ganglion is similar to that found in 
the posterior root ganglion in zoster of the trunk and limbs. 
Head and Campbell believe the affection to be an acute 
specific disease — a view suggested by the facts that it occurs 
in the course of recognised infective diseases, that it occurs 
endemically and epidemically, and that it rarely occurs a 
second time. It is probable that the affection may also have 
a toxic origin, as when arsenic has been taken for a long 
time, and in carbonic oxide poisoning. 

Treatment. — It is doubtful whether treatment has any 
influence in curing or in controlling the severity of an 
attack of herpes zoster ophthalmicus. Quinine in full doses 
should be given, and a 1 per cent, cocaine ointment made 
with equal parts of vaseline and lanolin should be smeared 
lightly over the affected part. Complications in the cornea 
or uveal tract are to be dealt with on the principles laid 
down in the chapters on diseases of those organs. The 
patient, unless the attack be a very mild one, should be 
confined to bed. 

* Syphilitic Affections of the Eyelids.— Pt •'unary 
Syphilitic Sores occur on the eyelids, usually near the margin 



DISEASES OF fHE EYE. [chap. vin. 



of the upper or lower lid, or at the inner or outer canthus, 
or may occupy the conjunctival surface of the eyelid. The 
first appearance is generally a small red swelling which the 
patient calls a " pimple," and which ulcerates and becomes 
characteristically indurated about its base. The margin of 
the ulcer is clean-cut, and its floor somewhat excavated, and 
covered with a scanty greyish secretion. Or, without any 
ulceration, the lid is swollen, greatly indurated, purple, and 
shiny ; and in these cases the diagnosis may be somewhat 
difficult. The prse-auricular and sub-maxillary glands are 
almost always swollen ; and this is a valuable, although not 
altogether positive, diagnostic sign, as it is seen also in tuber- 
cular diseases of the conjunctiva. The occurrence of the 
sore is followed by the usual constitutional symptoms of 
syphilis. Very rarely is there any permanent damage done 
to the eyelid. 

The most common modes of infection are by a kiss from a 
syphilitic mouth, or by a dirty finger. 

In view of the rarity of this affection, as also of inter- 
stitial keratitis in acquired syphilis, quite a number of cases 
have been recorded (and an instance has come under the 
notice of one of the authors), in which interstitial keratitis 
followed in the eye of which the eyelid had previously been 
the seat of a primary syphilitic sore. 

Treatment. — Locally, iodoform ointment, dusting with 
finely powdered iodide of mercury, or the black wash may 
be used ; while the usual general mercurial treatment is 
employed. 

Secondary Syphilis gives rise to ulcers on the margins 
of the lids, to loss of the eyelashes (madarosis), and to the 
secondary skin affections which attend it in other parts of 
the body. 

In Tertiary Syphilis a gummatous infiltration of the 
tarsus — so-called Syphilitic Tarsi tis — may occur, but it is 
a rare affection. One or both eyelids, in one or both eyes, 



CHAP. VIII.] 



THE EYELIDS. 



28? 



may be attacked. Without pain the lid becomes slowly 
and gradually hypertrophied, and the integument tightly 
stretched and hyperajmic. On palpation, which gives no 
pain, the tarsus can be felt, enlarged and of cartilaginous 
density. The palpebral conjunctiva is somewhat swollen, 
but through it the yellowish-white colour of the gummatous 
infiltration can be seen, if it be possible to evert the 
lid. Ptosis results, and the lid may be so hard and stiff 
as to render eversion impossible. The eyelashes fall out, 
and the pre-auricular gland is swollen. Although, as 
stated, the process is remarkable for its freedom from pain, 
yet severe pain may be experienced, should a rapid increase 
in the gummatous infiltration take place. Under treat- 
ment — which consists of iodide of potash and mercury — 
the infiltration disappears, and leaves a normal eyelid 
behind, or the tarsus may be somewhat atrophied as a 
result. 

* Vaccine Vesicles on the Eyelids are produced by acci- 
dental inoculation at the intermarginal part of the lid ; or on 
the outer surface of the lid, if the skin be abraded by thefinger- 
nail or otherwise. Sometimes the vesicle develops into a large 
ulcer with yellowish floor and hard and elevated margin. 
There is much pain, much swelling of the eyelid, and chemosis. 

Although distressing for a week or so while it lasts, the 
affection is not a dangerous one, further than that a cicatrix 
in the skin is left behind, and the eyelashes at the affected 
part are lost. 

Treatment. — A warm chlorate of potash lotion (gr. v ad ^j) 
is the best application. 

Rodent Ulcer (Jacob's Ulcer). — This disease commences 
as a small pimple or wart on the skin near the inner canthus, 
or over the lacrimal bone, as a rule; but it may also origin- 
ate in any other part of the face. The scab or covering 
of the wart is easily removed, and underneath is found a 
shallow ulcer with a well-defined indurated margin, the skin 



288 



DISEASES OF THE EYE. 



[chap. VIII. 



surrounding the diseased place being healthy. The progress 
of the disease is extremely slow, extending over a great 
number of years, and in the early stages the ulcer may 
even seem to heal for a time, but always breaks out again. 
In mild cases the ulceration may remain superficial ; but 
more usually it strikes deep, in the course of time eating 
away every tissue, even the bones of the face and the eye- 
ball. Tbe latter is often spared until after the orbital 
bones have gone. 

The disease is an epithelial cancer of a non-malignant or 
purely local kind. There is no tendency to infiltration of 
the lymphatics. It is rarely seen in persons under forty 
years of age. 

Treatment. — Extirpation of the diseased part with the 
knife, followed by the application of chloride of zinc, or 
of the actual cautery, used formerly to be employed ; and 
Bergeon's treatment, with the internal administration of 
chlorate of potash, and its local application as a lotion, 
was also used with benefit for the time. But all other 
measures have here given way to the X Ray treatment, 
wbich now enables brilliant cures to be effected in the 
majority of these terrible cases. Dr. W. S. Haughton, 
who is in charge of the X Bay department of the Victoria 
Hospital, has given us. the following description of the 
method which he finds to be the most successful in the 
treatment of rodent ulcer : — When the ulcer is large, 
lumpy, or prominent, it is advisable to remove as much 
as possible of its floor and margin by excision or cautery, 
so as to expose its growing base directly to the X Bays. 
The affected part is given two minutes' exposure to the 
X Bays every second day, until definite signs of X Bay 
reaction appear. The ulcer is exposed, at a distance of 
not less than six inches, through an accurately shaped 
window in a mask of lead foil. A layer of cotton-wool or 
other non-conducting material is placed between the patient's 



CHAP. 7IU.] 



THE EYELIDS. 



289 



skin and the lead foil. For superficial ulcers a soft 
X Rav tube gives the best results, when deep tissues 
are affected a bard tube is preferable. From 10 to 20 
sittings according to tbe extent and deptb of the ulcer, 
are usually necessary to effect a cure. Early cases are of 
course tbe most favourable for treatment, but in far 
advanced cases — even when the eyeball was gone, and the 
bones of the orbit extensively destroyed, with visible 
pulsations of the brain through the roof of the orbit — the 
growth of tbe disease has been arrested, and all pain and 
haemorrhage have been stopped. In l-odent ulcers of small 
extent radium is capable of effecting good cures. Two 
or three 5 mg. tubes of first quality radium are applied 
to the ulcerated surface for about half an hour, and at 
a different part of it at each sitting, which occurs at 
intervals of ten days to three weeks, until gradually the 
whole surface is brought to heal. The cicatrix left is 
remarkably soft and skin-like. 

* Thj^ondition known as Solid (Edema, or Elephantiasis 

Lympnailgioides of the Eyelids, is well represented in 
the accompanying picture (Fig. 125 x ) of a case under the 
care of Sir A. Critchett. It is a chronic tumefaction of tbe 
eyelids, most marked in the lower lids. The skin covering 
the swelling is smooth and pale, and suggests to the eye 
the skin of an cedematous lid ; but on palpation the swelling 
is found to be much more resistant than simple oedema. 
There is, almost invariably, a history of recurring attacks 
of facial erysipelas. These give rise to a permanent altera- 
tion of the lymph channels, and, each attack leaving its 
trace, an ever-increasing hypertrophy of the tissues of the 
eyelids takes place. 

Treatment. — Operative measures have been adopted in 
many instances with satisfactory results, both cosmetically 



1 Trans. Ophth. Soc. U.K., vol. xix. 

19 



290 



DISEASES OF THE EYE. 



[CHAP. VIII. 



and as regards the functions of the eyelids; but, unfortu- 
nately, in those cases which have remained under observation 
sufficiently long, the former condition gradually returned, 
as in Sir A. Critchett's case, in the picture of which the 
cicatrices of the operations can be seen. Multiple punctures, 




Fig. 125. 



collodion, pressure, etc., and many internal remedies have 
been tried in vain. 

* Plexiform Neuroma, or Neuro-fibroma is a rare 

disease of the eyelids. It is seen as a congenital growth 
which slowly increases in size. To the touch the tumour 
in general is soft, but contains many hard strings and 
knobs. Pressure on it is painful in some cases. It may 
attain great size, and may extend to the supra-orbital, 
temporal, and malar regions, giving rise to much disfigure- 
ment. Operation is indicated only if the tumour be mark- 
edly progressive, as a satisfactory result is not very 
attainable, and gangrene has followed in some cases, while 
in others, where the growth had to be followed deeply, severe 
hasmmorrbage has occurred. In some instances the tumour 



CHAP. VIII.] 



the i:yi:lids. 



291 



has invaded the orbit, and even the cavity of the skull, 
after absorption of the orbital roof. 

* Lymphoma or Lymphadenoma of the eyelids is usually 

seen as a bilateral and symmetrical disease, but it does 
occur on one side only in rare instances. It is frequently 
associated with leucaemia, or pseudoleucsemia, or it may 
be found in apparently bealtby individuals. It often invades 
the orbit, and its growth is exceedingly slow and quite 
painless. 

* Epithelioma, Sarcoma, and Lupus are all seen in the 
eyelids, but require no special description here. 

* Gangrene of the Eyelid is a rare condition. It may 
occur as a consequence of an infected wound of the lid, 
or from some general infection of the system, even in 
influenza, and has been seen as a result of excessive use 
of iced compresses. 

Clonic Cramp of the Orbicularis Muscle, or of a 

portion of it, is often seen, and is popularly known by the 
name of " life " in the eyelid. It is frequently due to over- 
use of the eyes for near work, especially by artificial light, 
or if there be defective amplitude of accommodation. 

Treatment should consist in the regulation of the use of 
the eyes for near work, and the correction by glasses of any 
defect in the accommodation. 

Blepharospasm, or Tonic Cramp of the Orbicularis 

Muscle, is commonly the result of irritation of the ophthalmic 
rlivision of the fifth nerve by reflex action, as in phlyctenular 
ophthalmia and some other corneal and conjunctival affections ; 
or from foreign bodies on the conjunctiva or cornea, etc. ; or 
it may continue for some time after the relief of any such 
irritation. It occurs, also, independently of such causes, and 
is then difficult to account for, unless as a hysterical symptom. 
Yet even in these obscure cases the spasm is probably often a 
reflex from the fifth nerve (i.e., teeth, or nose), and it will be 
found that pressure upon the supraorbital nerve at the 



292 



DISEASES OF THE EYE. 



[CHAP. VIII 



supraorbital notch may arrest the spasm ; or, if not there, 
then pressure on the infraorbital, temporal, malar, or inferior 
alveolar branch may have the desired effect. 

Treatment. — If the cause of the reflex cannot be ascertained, 
or if it have passed away, and if the cramp be still very 
distressing, stretching or resection of the branches of the 
fifth nerve, from which the reflex proceeds, may be tried. 
The operation of spino-facial anastomosis has been success- 
fully employed in some obstinate cases. 

Ptosis (7TT<wo-t?, a fall), or Blepharoptosis, is an inability 
to raise the upper lid, which then hangs down over the eye- 
ball. It is either congenital or acquired ; and in the latter 
case is most usually the result of paralysis of the branch of 
the third nerve supplying the levator. 

Persons affected with ptosis involuntarily endeavour to 
raise the eyelid by an over-action of the frontalis muscle. 
The drooping lid and elevated eyebrow give a'peculiar and 
characteristic appearance. 

The Causes of Paralytic Ptosis are similar to those of 
paralysis of other branches of the third pair, more especially 
exposure to cold draughts of air while the body is heated, 
and syphilis or rheumatism affecting the branch to the 
levator palpebral in its course. It may also be due to 
cerebral disease (see chap, xviii.). The branch to the 
levator may be paralysed alone, or in conjunction with other 
third-nerve branches, especially to the superior rectus, and 
the loss of power may be partial or complete. 

Some cases of bilateral ptosis in elderly people due to 
primary atrophy of the levator palpebral muscles have been 
recorded. The eyelids were elongated and thinned, so that 
the eyeball showed plainly through them. The loss of power 
had in each case been very slowly increasing for many years. 

The Treatment of a recent case of ordinary paralytic ptosis 
depends upon its cause. If this be syphilis, then a course of 
mercurial inunctions or of iodide of potassium ; if rheumatism, 



CHAP. VIII.] 



THE EYELIDS. 



293 



salicylate of soda or iodide of potassium — with, in either case, 
protection of the eye and side of the head by means of a 
warm bandage. Cases in which these remedies have failed, 
and which have become chronic, often demand operative 
treatment. Attempts have been made, with success in some 
cases, to obviate the inconvenience of ptosis by giving support 
to the lid by wire splints worn like an eyeglass or attached to 
the upper edge of spectacle-frames. 

Ptosis due to a cerebral lesion rarely comes within the 
scope of treatment. 1 

* Operative treatment is indicated in cases of paralytic ptosis 
— where other measures have produced no result — in ptosis 
adiposa, and in congenital cases. A very common proceeding 
consists in the excision of a sufficiently large oval piece of 
integument, its long axis lying in the length of the lid, with 
the subcutaneous connective tissue and fat, and, in paralytic 
cases, a small portion of the orbicular muscle. The fold of 
integument to be abscised is seized by two pairs of forceps — 
one of them held by an assistant — at the inner and outer ends 
of the lid, and by this means the necessary size of the fold is 
estimated. The abscision of the fold is performed with a 
pair of scissors, the margin of the wound lying close to the 
points of the forceps. The subcutaneous tissue, etc., is then 
removed, and the edges of the wound drawn together by 
a few points of suture. 

* Mule's Operation. — This operation is one of the many 
designed to enable the patient to derive more benefit from 
the effort of his frontalis muscle, which he is constantly 
making with so little result, by transferring its action more 
directly to the eyelid. A Knapp's clamp is applied to the 
lid to be operated on. The edge of the tarsus is then grooved 
''' '• third of an inch in length and deeply enough (o permit 



1 The value of ptosis as a localising symptom in cerebral disease will 
be treated of in chap. xvii. 




Fig. 128. Fig. 129. 

Fig. 120 shows intended track of wire. 

Fig. 127. — Wire loop D, with noedle ends passed upwards in thicknessof tarsus, 
and turned out at B n, tio be taken subcutaneously to E e by jttusis 
needles (c c) passed from above eyebrow. 

Fig. 12S shows wire at E in eye of ptosis noedle above eyebrow ; D, point of 
needle threadod with wire projecting at middle of lid before being drawn 

Up to E. 

Fig. 12D. — Completed except sinking wire knot permanently. 



prevent their being directed abnormally inwards. After 
grooving, tbe Knapp's clamp may be removed, and the lid 



CHAP. VIII.] 



THE EYELIDS. 



295 



drawn tense with the lid-forceps. Next, at each end of the 
groove (Fig. 127, A a), one sewing-needle with wire is passed 
upward half the width of the lid in the centre of the tarsus, 
so as to give a strong bite for the wire bend, then thrust 
forwards and outwards through the tarsus (at b b) and skin, 
the wire being drawn through the small incision made there. 
The ptosis needles (c c) are now pushed deeply from above 
the brow, a quarter of an inch apart, into the tiny apertures 
made for them by a thrust of the sclerotomy knife, then 
underneath the eyebrow downwards to the incision (b b) in 
the skin of the lid, through which the wire has already passed, 
and their points are also turned out there (Fig. 128, d). 
The wire is cut from the sewing-needles, threaded through 
the eyes in the points of the ptosis needles, withdrawn through 
the small apertures in the skin of the lid, and brought out 
above the brow at the points of entry of the ptosis needles 
(e). The wire bend is then drawn firmly into the grooved 
edge of the lid to allow of immediate healing, a little iodoform 
dusted on the groove and small incisions, the wire ends 
shortened, the apertures dressed with collodion, and iodoform, 
and a pad and bandage applied. After all swelling of the 
lid has passed, the permanent effect may be secured by tying 
the wire after careful adjustment of the lid, and sinking it 
into a small skin incision made for the purpose (Fig. 129). 
Harman uses fine gold chain which is more flexible than wire. 

*Birnhacher's Operation. — An incision, with its convexity 
upwards, is made in the skin corresponding to the upper edge 
of the tarsus. Three sutures with a needle at each end are 
passed through the upper border of the tarsus, so as to 
form three loops, one central and two lateral ; the two 
needles of the central loops are passed vertically upwards 
under the skin, and are brought out quite close to one 
another in the eyebrow. The lateral loops are treated in 
the same way, but are made to diverge on each side from 
the central one, instead of being parallel. The ends of the 



296 



DTSKASKS OF THE EYE. 



[CHAP. VIII. 



threads are tied over a small roll of lint, and tightened 
until the edges of the lids just touch when the patient 
closes the eye. They may he left in from twenty to twenty- 
five days. 

Congenital ptosis is generally present in both eyes. It is 
due in some cases to an imperfect development of the levator 
palpebral, and in others to an abnormal insertion of this 
muscle, its tendon being attached to the tarsus too far back. 
Either Birnbacher's or Panas' operation may be employed, 
and Eversbusch has proposed the following proceeding more 
particularly for congenital ptosis: — 

* Eversbusch' s Operation for Congenital Ptosis (Figs. 130 and 
131). — The object of the operation is to increase the power of 
the levator by advancing its insertion, or rather by doubling 
it down over the tarsus, to which it forms fresh adhesions. 
Knapp's lid-clamp is applied, the plate being passed well up 
into the fornix ; and, before the ring is screwed down, the 
skin of the lid is drawn down, so that its prolongation just 
under the eyebrow may be forced into the instrument. The 
skin and the underlying orbicularis are now divided in the 
entire width of the lid, parallel to its free margin, and at 
a distance half-way between this margin and the eyebrow. 
The skin and the subjacent muscle are then separated up, both 
upwards and downwards, for 4 mm. in each direction, so that 
the insertion of the levator may be well exposed. A suture 
with a small curved needle at either end is then introduced, 
by means of one of these needles, horizontally into the tendon 
at its insertion, and near the centre of the latter, in such 
a way that about 2\ mm. of the tendon may be included 
in the suture. Each needle is now passed vertically down- 
wards between the tarsus and orbicularis, and brought out 
at the free margin of the lid at a distance from each 
other of about 2\ mm. Two more such double sutures, 
one in the temporal, the other in the nasal, third of the 
tendon, are similarly applied. The margins of the hori- 



CHAP. V111-] 



THE EYELIDS. 



297 



zontal skin and muscle wound are now drawn together, and 
then the three sutures are closed tightly. It is desirable 
to slip glass heads over the ends of the sutures before tying 
tlieni, to prevent cutting into the margin of the lid. Both 
eyes are bandaged, and the sutures left in for a week or more. 

While the foregoing, and other, operations relieve the 
ptosis, they are liable to give rise to some unsightly cicatrices, 
and are sometimes not permanent in their effect. With 




Fig. 130. Fig. 131. 

I, levator palpebrae ; o, orbicularis. 



a view to obviate these drawbacks, Carl Hess has devised 
the following operation. 

11 Operations. — The eyebrow having been shaved, 
an incision (a a, Fig. 132) is made in its whole length, and 
carried through the skin and subcutaneous tissue ; and, 
starting from this incision, the skin of the lid is separated 
with the scalpel from the underlying orbicular muscle 
nearly as far as the ciliary margin (dotted line in Fig. 132). 



298 



DISEASES OF THE EYE. 



[CHAP. vni. 



When the haemorrhage has ceased, three silk sutures, 
each armed with two needles, are introduced, one at the 
centre and one towards either end of the eyelid, and 
about half-way between the eyebrow and lid margin 
(b, Fig. 132), or somewhat nearer the latter. The needles of 
each suture are inserted about 5 mm. apart, and, being 
passed from without inwards through the skin, they are 
brought out in the space made by the skin dissection. The 
needles are now passed deeply under the upper border of the 
incision in the eyebrow, and brought out a few millimetres 
above it (at points represented by three pairs of dots in 




Fig. 132. 



Fig. 132). The two ends of each suture are tied over a small 
roll of lint or a bit of rubber drainage tube, and drawn 
tightly enough to relieve the ptosis by producing a fold in 
the skin flap. The wound in the eyebrow is united by 
some points of suture. The sutures are allowed to remain 
for eight or ten days. The permanent result depends on 
the union and cicatrisation of the extensive raw surfaces 
in their new position. The operation causes little or no 
disfigurement, as the artificial fold falls in about the same 
situation as that which is present in the normal eyelid, 
while the cicatrix in the eyebrow is concealed by the hairs 
when they have grown again. In Figs. 133 and 134 a section 
of the eyelid after tightening of the sutures is represented. 
*A remarkable condition is Congenital Ptosis, with Associated 



CHAP. VIII.] 



THE EYELIDS. 



299 



Movements of the Affected Eyelid, during the action of certain 
muscles. There are only about thirty cases of this on record. 
It is most commonly the left lid which is affected, and the 
paralysis may be congenital or acquired. Three conditions 
have been observed — viz., (1 ) elevation of the drooping lid 
when the eye is adducted, (2) when the eye is abducted, or 
(3) when the mouth is opened. A synchronous contraction of 
the pupil has been noticed in some cases, while in some 
the elevation of the lid occurs also with a lateral motion 
of the jaw, and with deglutition. Gower's explanation is 




Fig. 133. Fig. 134. 



Fig. 133.— The needles are passed in at a through the skin of the 
lid, and brought out at a' through the skin and subcutaneous 
tissue above the eyebrow. 

Fl0. 134. — When the sutures are tightened a is closely approximated 
to a'. 

that in these cases the levator is not wholly supplied by the 
third nerve, but partly also by nerve fibres which take their 
origin in the nucleus of the fifth pair, and which also supply 
the external pterygoid and digastric muscles. But this 
theory does not hold good in all cases, for Bull describes 
a case in which the lid was raised when the head was 
bent back, thus stretching the digastric, and he regards these 
as associated or reflex movements. In some instances the lid 
can be raised voluntarily on closing the other eye. Needless 
to say, no remedy can be applied for relief of this condition. 
The term ptosis is also given, although not very correctly, 



300 DISEASES OF THE EYE. [CHAP. vm. 



to cases in which increased weight of the lid causes it to 
droop, as in conjunctival affections, or where a tumour has 
formed in the eyelid, or where there is a hyper-development 
of the subcutaneous fat. 

* Lagophthalmos (Xayco?, a hare, as it was supposed that 
this animal sleeps with its eyes open ; o<£#aX,/io?), or inability 
to close the eyelids, is most commonly due to paralysis of the 
portio dura, and is then associated with the other symptoms 
of the latter affection. On an effort to close the lids being 
made, the eyeball is rotated upwards under the upper lid, 
owing to the associated action of the superior rectus ; and in 
sleep tbis upward rotation also occurs — a fact which explains, 
to a great extent, the immunity of the cornea from ulceration 
in many of these cases. Lagophthalmos may also be due to 
orbital tumours pushing the eyeball forwards, to exophthal- 
mic goitre, to staphyloma, or to intraocular growths distending 
the walls of the eyeball — in all of which conditions the eyelids 
are often mechanically prevented from closing over the eye- 
ball, or can be closed only by a strong effort of the will. The 
danger to the eye depends upon the tendency to idceration of 
the cornea from its dryness, caused by exposure to the air, 
and from foreign substances not being removed from it by 
nictitation. 

In cases of non-paralytic lagophthalmos, protection of 
the cornea by keeping the eyelids closed with a bandage, or 
by inserting a few epidermic sutures in the margins of 
the eyelids to draw them together, should be our first 
care. Tarsorapby may be employed in those cases where 
circumstances indicate that it would be useful — e.g., iu some 
cases of exophthalmic goitre, or of staphylomatous eyeball. 

In paralytic cases, the primary cause of the paralysis 
(syphilis, rheumatism, etc.) must be treated so long as there 
is a prospect of restoring power to the muscle. Locally, 
galvanism and hypodermic injections of strychnia may bo 
employed. During cure the cornea should be protected 



CHAP. VIII.] 



THE EYELIDS. 



301 



as above. In incurable cases, the opening of the eyelids 
must be reduced considerably in size by an extensive 
tarsoraphy, or by the method proposed by Pfliiger. 

The Operation of Tarsoraphy consists in uniting the margins 
of the upper and lower lids in the neighbourhood of the 
external commissure, so as to reduce the size of the opening of 
the eyelids. The commissure should be caught between the 
hnger and thumb, and the edges of the lids approximated, 
so as to enable the operator to form an estimate of the 
required extent of the operation. A horn spatula is then 
passed behind the commissure, and the necessary length of 
the margin of each lid, including the bulbs of the cilia, 
abscised with a sharp knife. The raw margins are then 
brought together with sutures. 

Pfliiger s Method consists in passing one, two, or even three 
double sutures subcutaneously around the eyelids, abovit 5 
mm. from their margins. The ends are drawn together, so 
that the eye is concealed by the pouch thus formed, and 
tied. From time to time tbe sutures are tightened, until 
finally they cut through, and by this means a subcutaneous 
ring-cicatrix is produced. Should the first ring-cicatrix not 
sufficiently close the eyelids, the operation can be repeated 
even more than once again. The method is tedious and 
painful. 

Symblepharon icrvv, together ; f3\e<papov, the eyelid) is an 
adherence, partial or complete, of the eyelid to the eyeball. 
It is usually the result of burns of the conjunctiva by fire, 
acids, or lime. The shortening of the conjunctival sac, 
which is seen as the result of pemphigus or of granular 
ophthalmia, and which is described above under the heading 
of Xerophthalmos, is not properly termed symblepharon. 
If the symblepharon interfere seriously with the motions 
of the eyeball, or if it cause defect of vision by obscuring 
the cornea, it becomes desirable to relieve it by operation 
Should it consist of a simple band stretching from lid to 



302 



DISEASES OF THE EYE. 



[CHAP. VIII. 



eyeball, it may be severed by ligature, and if the band 
be broad, two ligatures may be employed, one for either 
half. A symblepharon which occupies a considerable surface 
cannot be got rid of in this way ; and for such cases a 
transplantation procedure like that of Teale may be employed, 
the great difficulty in dealing with these cases being the 
tendency there is to re-union of the surfaces, unless one or 
both of them be carpeted with epithelium. 

* In Teale s Operation, if we suppose the case to be similar 
to that represented in Fig. 135, an incision is carried along 
the line of the margin of the cornea at A, through the whole 
thickness of the symblepharon, and the lid is dissected off 




Fig. 135. Fig. 13G. 1 , 



from the eyeball as far as the fornix. Two conjunctival 
flaps are now formed, as at B and C in Fig. 136, and one of 
them (Z?) is turned to form a covering for the wounded sur- 
face of the inside of the eyelid, while the other (C) is used 
to cover the bulbar surface (Fig. 137), the flaps being held in 
their places by fine sutures. That part of the symblepharon 
which is left adherent to the cornea soon atrophies and 
disappears. No great tension of the flaps should exist as 
they lie in their new positions. 

Teale, again, has suggested the formation of a bridge-like 



1 Mr. Teale now makes his flaps, as in Fig. 13G, wider tban he originally 
did. He has been so kind as to alter tbis drawing with his own band 
for this work. 



CHAP. VIII.] 



THE i:yfjads. 



303 



conjunctival flap above the cornea, and the removing of it 
across the latter to cover the loss of substance situated below. 
After the sutures to keep the flap in its place have been 
introduced, the latter is separated at its bases. 

A simple plan, which would be applicable to such a case 
as that depicted in Fig. 135, where the adhesion is not very 
extensive, and perhaps even to some more extensive ones, 
consists in dissecting the con- 
junctival process off the cornea, 
and then turning it down on 
the raw inner surface of the 
under lid, and fastening it there 
with a suture or two. We have 

done this with complete satis- 
„ . Fig. 137. 

taction. 

* Harlan's Operation. — This is specially applicable to exten- 
sive symblepharon of the lower lid, and differs from the 
foregoing operations in that it provides a covering of skin, and 
not of mucous membrane, for the raw surface of the under- 
bid. Operations on the same principle have been proposed by 
Snellen and by Kuhnt. An incision (A B, Fig. 138) through 

the whole thickness of the eye- 
lid, and corresponding in length 
to the latter, is made along the 
lower margin of the orbit. Below 
this a skin flap (C D) is then 
formed. The flap is dissected 
up, and the incisions are carried 
a little more deeply as A B is approached, to enable the flap 
to turn the more readily. The flap is then turned up as 
on a hinge, slipped through the buttonhole, and sutured 
securely to the inner surface of the under-lid. After a time 
the skin surface turned towards the eyeball becomes consider- 
ably modified, so as to be somewhat like mucous membrane. 
The bare space left by the removal of the strip of skin 





Fig. 138. 



304 DISEASES OF THE EYE. [chap. viii. 



is covered without strain by making a small horizontal 
iucision (D E) at its outer extremity, and forming a sliding 
flap. 

Transplantation Operations. — The transplantation of 
mucous membrane from the lips or cheek has been used 
in extensive syinblepharon, but the drawback to mucous 
membrane flaps, where two opposing surfaces have to be 
covered is that when the superficial epithelium of the mucous 




Fig. 139 (de Weaker). 



membrane is thrown off there is danger of the surfaces 
uniting. Thiersch and other skin flaps are preferable (see 
chap. xix.). 

Blepharo phimosis (/3\e<f>apov, eyelid; (plfimo-is, narrowing) 
is a contraction of the outer commissure of the lids, with 
consequent diminution in size of the opening between the 
latter • and is commonly due to shortening of the skin, from 
long-continued irritation of it, caused by the discharge in a 
case of very chronic conjunctivitis. 

It is remedied by a Canthoplastic Operation. The outer com- 



CHAP. VIII.] 



TffH EYELIDS. 



305 



missure is divided in its entire thickness, in a line which is a 
prolongation of the line of junction of the lids when closed, by 
a single stroke of a strong straight scissors, one blade of which 
has been passed behind the commissure. The integnmental 
incision should be made a little longer than that in the con- 
junctiva. An assistant then draws the upper lid up and the 
lower lid down, so as to make the wound gape. The conjunc- 
tival margin and the dermic margin are now united in the 
centre by a point of suture (C, Fig. 139), while two more sutures 
(A and B) are applied, one above and the other below the 
first. This operation is also employed in cases of granular 
ophthalmia and of purulent conjunctivitis, when it is desired 
to relieve pressure of the eyelid on the globe. 

Distichiasis (S19, twice; o-t/%o?, a row) and Trichiasis 

(Tpt'^o?, a hair). — The first of these terms indicates the 
growth of a row of eyelashes along the intermarginal por- 
tion of the lid in addition to the normal row ; while trichiasis 
indicates a false direction given to the true cilia. Both con- 
ditions are often found co-existing, and often, too, they are 
present along with entropium. They may both be produced 
by chronic blepharitis (p. 276), or by chronic granular ophthal- 
mia (p. 162). Some cases of congenital distichiasis and trichi- 
asis have been recorded. The symptoms the false cilia 
produce, and the dangers to the eye attendant on them, 
are due to their rubbing on the cornea, which causes pain, 
blepharospasm, and opacity of the cornea, or even ulceration 
of it. 

Operations for Distichiasis and Trichiasis : — 
Epilation. — The false cilia may be pulled out with a 
foi •ceps ; but this cannot be regarded as a cure, for the 
hairs grow again. 

Electrolysis. — A needle is attached to the negative pole, 
and its point passed into the bulb of the eyelash to be 
removed, the positive pole being placed on the temple. On 
closure of the circle, if the battery be working properly, 

20 



306 



DISEASES OF THE EYE. 



[CHAP. VIII. 



bubbles of gas should rise up round the needle, and a 
slough forms at the root of the hair, which becomes loose, 
and is removed. It does not grow again, for the bulb 
is destroyed. Each hair must be 
separately operated on. The pro- 
ceeding is very valuable where 
only a few cilia «are to bo dealt 
with. 

Excision. — When some half-dozen hairs close 
together are growing wrong, the simplest and 
best plan is to completely remove them by 
excision of the corresponding portion of the 
ciliary margin. A fine knife is passed into the 
intermarginal region at the place corresponding to 
the hairs to be dealt with, and a partial division 
of the lid into two layers, as in the Arlt-Jaesche 
operation (vide infra), is effected. A V-shaped in- 
cision in the skin of the lid is then made, including 
the erring hairs, the whole flap is excised, and the 
margin of the loss of substance drawn together 
with sutures. 

In cases of distichiasis or trichiasis involving 
the whole length of the eyelid, removal of the 
marginal portion of skin containing the bulbs of 
all the eyelashes, true and false (Flarer's opera- 
tion), is not to be recommended — unless, occa- 
sionally, in the underlid — because it unnecessarily FlG - 14 0. 
deprives the eye of an ornament, and of a protection against 
glare of sun and foreign bodies. 

Transplantation, or Shifting, of the marginal portion of the 
integument containing the hair bulbs, true and false. One 
of the oldest and most valuable operations of this kind is that 
of Jaesche, modified by Arlt. It is performed as follows : — 
Knapp's, or Snellen's, clamp (Fig. 140) having been applied to 
prevent bleeding, the lid in its whole length is divided in 



CHAP. VIII.] 



THE EYELIDS. 



307 



the iutermarginal part into two layers (Fig. 141), the anterior 
containing the orbicular muscle and integument with all the 
hair bulbs, the posterior con- 
taining the tarsus and conjunc- 
tiva. The incision in the 
intermarginal portion is about 
5 mm. deep. A second in- 
cision is now made through 
the integument of the lid, 
parallel to its margin, and 
from 5 to 7 mm. removed from 
it. This incision also extends 
the whole length of the lid. 
A third incision is carried in 
a curve from one end to the 
other of the second incision. 
The height of the curve is 
proportional to the effect re- 
quired, varying from 4 mm. 
to 7 mm. The piece of integument included between the 
second and third incisions is dissected off with forceps and 
scissors, without any of the underlying muscle being touched, 
and the margins of the loss of substance are brought together 
by sutures. By this procedure the lower portion of integu- 
ment, containing the hairs and their bulbs, is drawn up and 
away from contact with the cornea. 

Van MUlingen's Operation consists in splitting the eyelid, 
as in the Arlt-Jaesche operation, from end to end, sufficiently 
to produce a gap (/J, Fig. 142) 3 mm. in width at the central 
part of the lid, and gradually becoming narrower towards the 
canthi. The gap is kept open by sutures passed through 
folds of skin on the upper lid (a a a), by means of which 
also the lid is prevented from closing for twenty-four hours 
at the least. As soon as the bleeding has ceased, a strip of 
mucous membrane of the same length as that of the lid, and 




Fig. 141. 



308 



DISEASES OE THE EYE. 



[chap. viii. 



2 to 2| mm. in breadth, is cat out with two or three snips of 
a curved scissors from the inner surface of the patient's under- 
lip, on which a Knapp's clamp has been placed to prevent 
bleeding, and is introduced at once into the gap in the inter- 
marginal space. It should then be pressed into position with 
a probe. According to Van Millingen, sutures are superfluous ; 
but they are desirable for the sake of security, and do no 
harm. It is important, in order to obtain a neat effect, to 




KlG. 142. 



clean the fat and submucous tissue from the flap before 
applying it ; while this is being done the flap should lie on a 
warm porcelain plate. The eyelid is then covered over with a 
piece of lint, on which is spread a thick layer of xeroform 
vaseline, and over this is placed a wad of cotton-wool and a 
bandage. 

It is not advisable to transplant small strips of mucous 
membrane if the trichiasis be partial, as partial trichiasis is 
often only the commencement of complete trichiasis, and 
therefore, in these cases, the filling up of the entire length 
of the intermarginal space with a flap of mucous membrane 
should be effected. One or two fine sutures, which serve to 



CHAP. VIII.] 



THE EYELIDS. 



309 



unite the margins of the wound iia tho lip, arrest the 
bleeding at once, and accelerate union of the part, which is 
generally completed in twenty-four hours. 

This method is very effectual in permanently providing a 
good intermarginal space, and in thus definitely relieving the 
condition. 

Entropium (ev, in; rpeirw, to turn), or Inversion of 

the Eyelid, is due to organic change in the conjunctiva or 
tarsus, or to spasm of the palpebral portion of the orbicular 
muscle. A large proportion of the former class of cases is 
the result of chronic granular ophthalmia, and is most common 
in the upper lid. Spastic entropium occurs in the under lid 
only. It is frequent in old people (senile entropium) from 
relaxation of the skin of the eyelid, and is also produced by 
the wearing of a bandage after operations. 

Treatment. — Organic entropium, in which the tarsus of the 
upper lid is not distorted, can often be corrected by one 
of the methods described for trichiasis and distichiasis. 
But many of these cases are accompanied by, or rather 
are due to, abnormal curvature with hypertrophy of the 
tarsus. 

In such cases the operation must include an attack on 
the tarsus itself. 

Snellen's Operation. — Knapp's clamp is applied. About 
3 mm. from the margin of the lid, and parallel to it, an 
incision is made through the skin alone, extending the whole 
length of the lid. The orbicular muscle is exposed by dis- 
section of the skin upwards, in order to promote retraction of 
the latter, and along the edge of the lower margin of the 
wound a strip about 2 mm. broad of the orbicular muscle 
is removed, and the tarsus to the same extent is exposed to 
view. A wedge-shaped piece, corresponding to the exposed 
part of the tarsus, is now excised from it with a very sharp 
scalpel, the edge of the wedge pointing towards the con- 
junctiva, which latter, however, is left intact. The 



310 



DISEASES OF THE EYE. 



[CHAP. VIII. 



hypertrophy of the tarsus, which is always present, 
facilitates this procedure. A silk suture carrying a 
needle on each end having been prepared, one needle is 
passed from within outwards through the band of muscle 
and integument left at the margin of the lid. The second 
needle is also passed from within outwards through the 
upper lip of the tarsal loss of substance, and then from 
within outwards through this same marginal band, at a 
distance of about 4 mm. from the point of exit of the first 
needle. The ends of the suture are now tied together, a small 




Fig. 143. Fig- 144. 



bead having first been strung on each to prevent it from 
cutting through the skin. Three such sutures are employed. 
The accompanying figures (143 and 144) make the foregoing 
description more intelligible. 

Berlin's Operation.— Knapp's clamp is applied. The first 
incision lies 3 mm. above the margin of the lid, extends its 
whole length, and divides it in its entire thickness, including 
the conjunctiva. The skin and muscle at the upper edge of 
the wound are pushed or dissected up so as to expose the 
tarsus. The upper edge of the tarsal incision is now seized 
at its centre with a finely toothed forceps, and an oval piece 



CHAP. VIII.] 



THE EYELIDS. 



311 



with the adherent conjunctiva, about 2 to 3 mm. wide in its 
widest part, and in length corresponding with that of the 
eyelid, is excised from it with a fine scalpel. The wound is 
closed with three sutures through the skin. If it be thought 
desirable to increase the effect, a skin-flap may be excised 
from the lid. The objection to this operation, that a portion 
of the mucous membrane is removed, is not of importance. 
The method is a good one. 

Spastic Entropium of the lower lid, as the result of 
bandaging, usually disappears when the use of the bandage 
is given up, or, if the bandage must be continued and should 
the inverted lid cause irritation, a dermic suture at the 
palpebral margin and fastened to the cheek below will give 
relief. 

Senile Entropium of the lower lid is, of the spastic kinds, 
the one which most commonly demands operative interference. 
The methods in general use for it are : — 

The Excision of a Horizontal Piece of Skin, with a portion 
of the underlying palpebral part of the orbicular muscle, so 
as to give rise to sufficient cicatricial contraction to draw 
the margin of the lid outwards. Unfortunately this often 
does not effect a permanent cure, relapse taking place after a 
time. 

The foregoing, and other such measures, produce a good 
result at the time, but are sometimes followed by recurrence 
of the entropium. Hotz believing the cause of this to be that 
the cicatrix, whether dermic or dermo-muscular, upon which 
the result depends has no point d'appui ; and consequently, 
while it may draw the eyelid out, is liable to draw the skin 
of the cheek up, and thus to neutralise its desired effect, 
has proposed the following ingenious operation : — 

Jfotz's Operation. — A horn spatula is inserted under the lid 
and then, at 4 to 6 mm. below the margin of the latter, a 
horizontal incision is made through the skin from the inner 
to the outer end of the lid. This incision is at the boundary 



312 



DISEASES OF THE EYE. 



[chap. viii. 




Fig. 145. 



between the palpebral and orbital portions of the orbicular 
muscle, and just over the lower margin of the tarsus. An 

assistant then draws the 
upper edgo {a, Fig. 145) of 
the wound upwards with a 
forceps, while the surgeon 
draws the lower edge (b) 
downwards, in this way 
exposing and stretching the 
orbicular muscle. A few 
strokes of the knife in the 
direction of the incision are 
now sufficient to separate 
the palpebral portion (I) of 
the muscle from the orbital portion (j>), and to lay bare 
the lower edge of the tarsus (t), which has a yellowish 
tendinous appearance. That part of the palpebral portion 
of the muscle which covered the lower edge of the tarsus, 
and which was drawn up with the palpebral edge of the 
first incision, is now removed with forceps and scissors, to 
the extent of about 2 mm. in width, through the whole 
length of the lid. All such muscular fibres, also, which may 
still adhere to the lower third of the tarsus must be care- 
fully cleaned off, and now the palpebral skin may be brought 
into union with the tarsus. Four sutures are generally applied, 
about 5 mm. apart. The needle is passed through the palpe- 
bral skin, close to the margin of the wound (at a). The bare 
tarsal edge is then seized in the forceps, the needle placed 
perpendicularly on it (at cl), and carried through it by a short 
downward curve until its point appears (at c) below the tarsus 
in the tarso-orbital fascia (/). The needle is now passed out 
through the lower edge of the incision (at b), care being taken 
that none of the fibres of the orbital portion of the muscle are 
included in the suture. Upon the suture being tightly closed, 
the edges of the skin wound are drawn into the tarsus, and 



CHAP. VIII.] 



THE EYELIDS. 



313 



become adherent to it. The sutures may be removed about 
the third day. If the first incision be placed too far from 
the margin of the lid, there will be no result, as the traction 
upon the palpebral skin will be too slight. If the incision 
be placed too close to the margin, the traction may be so 
great as to interfere with the union of the skin and tarsus. 
In this operation the tarsus affords the fulcrum, which Hotz 
thinks is wanting in other methods. The tarsus of the lower 
lid is sometimes very little developed, and then we find that 
the result of the operation may be disappointing. 

Ectropium or Eversion of the Eyelid. — Of this there 

are two chief kinds: (1) 'Muscular, or Spastic, which affects 
the lower lid only ; (2) Cicatricial. 

Muscular ectropium occurs only in the lower eyelid and 
may have its starting point in oedema of the conjunctiva, 
which everts the edge of the eyelid, and this eversion becomes 
increased and encouraged by spasm of the palpebral portion 
of the orbicular muscle, so that the term palpebral para- 
phimosis might be given to the condition. In the recent 
stage it may generally be remedied by suitable conjunc- 
tival measures. In chronic cases operative measures are 
usually required. 

Muscular ectropium is often seen in old people, and is 
then given the name of Senile Ectropium. Here it is due 
to atrophy of the palpebral portion of the orbicularis of the 
lower lid, and relaxation of the skin of the face. When 
these have resulted in slight eversion of the inferior punctum, 
a flowing of tears is produced, causing some excoriation 
of the skin and edge of the lid, which then increase the 
tendency to ectropium. If the condition be not extreme, 
with secondary changes in the conjunctiva, slitting up of the 
canaliculus, with the use of a boric ointment for the lids 
and mild astringents for the conjunctiva, will give much 
relief. In pronounced cases a more active treatment of the 
conjunctiva, and the performance of tarsoraphy, or the ap- 



314 



DISEASES OF THE EYE. 



[CHAP. VIII. 



plication of Snellen's sutures, or one of the other operations 
described below, are demanded. Muscular ectropium is also 
caused by paralysis of the orbicular muscle. 

Snellen s Sutures. — A silk ligature is threaded at either end 
with a needle of moderate size and curve. The point of one 
of these needles is passed into the most prominent point of 
the exposed and everted conjunctiva, and brought out through 
the skin 2 cm. below the edge of the lower lid. The other 
needle is entered in the same way 5 mm. from the first, and 
made to take a nearly parallel course, the points of exit on 
the cheek being 1 cm. apart. Equal traction is applied to 
each end of the suture, while the lid is assisted into its 
place by the finger. The suture is tied on the cheek, a small 
roll of sticking-plaster having been inserted under it, to 
protect the skin from being cut. Two, or even three, such 
sutures may be required, and they are allowed to remain for 
several days. 

Freeland Fergus Method. — Fergus points out that the two- 
thirds of the exposed conjunctival surface of the lower eyelid, 
from the fornix towards the free margin, are usually com- 
paratively healthy, the marginal third alone being diseased. 
He has devised the following procedure, which consists in 
excision of the diseased tissue. An incision is made through 
the conjunctiva from the inner to the outer canthus, de- 
marcating its healthy from its diseased portion. With 
forceps and scissors the conjunctiva covering the healthy 
portion of the eyelid is freed from the underlying structures 
right down to the region of the retro-tarsal fold. The 
hypertrophied tissue is next excised throughout its entire 
extent, so as to restore as it were the original margin of the 
lid, and finally the conjunctiva is drawn up and secured by 
a few points of suture to the margin. The success of the 
operation depends on the thoroughness with which the 
excision of the hypertrophied tissue is carried out. 

Kuhnt's Operation for Senile Ectropion is an admirable 



CHAP. VIII.] 



THE EYELIDS. 



315 



one. It consists in splitting the lower lid in its central 
third, so that the conjunctiva and tarsus are left in the 
posterior layer, while the anterior layer contains the orbicu- 
laris and the skin. A triangular piece, the base of which 
is formed by the margin of the lid, is then excised from the 
posterior layer, and the margins of the loss of substance in the 
latter are brought together by three or four points of suture. 
Lest they should give way too soon, it is necessary to place 
these sutures very securely. A puckering of the anterior 
layer, opposite the line of sutures in the posterior layer, 
is produced, but subsequently disappears, and a suture which 
unites the most prominent point of the pucker and the 
margin of the tarsus assists in this. Or, if the lid be 
split, say, to an extent twice as long as the base of the 
triangular piece to be excised, the puckering can be dis- 
tributed at either end of the incision. By reason of the 
shortening of the lid as the result of this excision the 
eversion is corrected. We frequently use this operation, and 
always with gratifying results. 

Kenneth Scott's Operation. — The external canthus and 
ti-sues beyond are thoroughly divided by a pair of strong 
scissors. The lower eyelid, which is usually the affected one, 
is then seized and its margin stretched sufficiently outwards, 
parallel to the border of the other lid, so as to restore the 
palpebral aperture to its proper appearance ; the portion of 
eyelid margin thus made to extend beyond the site of the 
external canthus is removed, along with its contained eye- 
lashes, by slicing it with a sharp knife. The upper and 
lower eyelids are then brought together, so that the original 
outer extremity of the upper eyelids approximates exactly to 
the new extremity of the lower eyelid. They are secured in 
this position by passing a silver wire suture vertically down- 
wards through the substance of the upper lid, continuing it 
out through that of the lower one, and then twisting the 
ends firmly together. Two of these retaining stitches may be 



316 



DISEASES OF THE I. > /.. 



[chap. viii. 



introduced close together if necessary. The edges of 
divided skin, along with the deeper muscular tissues, 
including that part which recently formed the outer end 
of the affected eyelid, are simply stitched together with a 
continuous fine silk suture. 

No dressing other than a repeated dusting with some fine 
antiseptic powder need be used. The silk stitches may be 
removed in six days' time, the silver ones being left in 
for five or six days longer. Scott states there is never 
any puckering apparent beyond the newly formed canthus, 
and the small linear cicatrix is lost amongst the other 
lines often found there. 

Cicatricial ectropium is caused by scars in the eyelid from 
caries of the orbit, or from wounds or burns, which destroy 
the integument of one or both eyelids. A common event 
is cicatricial ectropium caused by burns of the face which 
epileptics or children who have fallen into the fire have 
acquired. In these cases the burnt skin is replaced by a 
granulating surface, and when cicatrisation of this com- 
mences the free margin of the upper lid is drawn up towards 
the eyebrow, and that of the lower lid down towards the 
cheek, the conjunctival surface of the eyelids in consequence 
becoming everted, and the cornea exposed, as the eyelids 
cannot now be closed. 

Many operations have been proposed for the relief of this 
condition, but the only one we recommend is that by Skin 
Transplantation after the, Method of Wolfe. It is performed 
as follows : — 

In the first place the eyelid — let it be the upper eyelid — 
is dissected down into its place to the utmost limit, so that 
the most extensive raw surface possible may be obtained. 
The margin of the lid, having been drawn over the 
lower lid, is fastened to the cheek with three points 
of suture. A portion of skin, suited as regards 
shape, and about one-third larger (to allow for shrinkage) 



CHAP. VIII.] 



THE EYELIDS. 



317 



than the raw surface of the eyelid, is then taken from the 
inside of the arm, and having been carefully freed of all 
its subcutaneous fat and connective tissue, is laid upon the 
raw surface, and secured to it by a large number of fine 
interrupted sutures around the margin. Or, if the margin 
of the skin surrounding the raw surface be dissected up, 
the edge of the graft can be slipped under it, and secured 
in its place by this means. A non-irritating dry or oint- 
ment dressing is applied, and the graft usually heals on 
in the course of a few days. This method of grafting was 
introduced by Wolfe and Lefort, and we employ it in 
all these cases with most satisfactory results. 

It is important to preserve and utilise any part of the skin 
of the eyelid which remains, especially its ciliary border 
with the eyelashes. The thorough cleaning of the flap 
from its subcutaneous fat and connective tissue is also 
important, as otherwise an unsightly and lumpy effect is 
produced when the flap has healed on. While this cleaning 
is being done the flap should lie on a warm sterilised 
porcelain plate. The flap should not be applied to the raw 
surface until all oozing of blood from the latter has ceased, 
but this is usually the case by the time the operator has 
prepared the skin flap from the arm. 

The transplantation of a flap with pedicle from the 
forehead, temple, or cheek is also used to repair an eyelid ; 
but, owing to the thickness of the integument, the result 
is cosmetically less satisfactory than that given by a graft 
from the arm, while the tendency to shrink is quite as great. 

Some prefer Thiersch grafts to dermic grafts, and 
state they are more easily applied to the raw surface, 
and do not differ in colour from the surrounding skin 
when healing is completed. It is desirable to obtain 
one continuous graft of the whole size of the wounded 
surface. 

Ankyloblepharon (dyxuXr), a string; fiXefaipov, an 



318 



DISEASES OF THE EYE. 



[CHAI>. VIII. 



eyelid) is a uniting of the upper and lower eyelids along their 
margins. It may be partial or complete, and often goes with 
symblepharon. Like the latter, it is usually caused by burns 
and ulcers. 

The condition can only be relieved by operation, of which 
the result is often unsatisfactory, owing to the difficulty of 
preventing re-union taking place at the canthi. To avert this 
it is always necessary to cover the wounded surface with 
conjunctiva or skin. 

Injuries of the Eyelids. — All kinds of injuries of the 
eyelids (contusions, incisions, bums, etc.) are common. 

In consequence of the looseness of the integument, oedema 
and ecchymosis, one or both, are often seen in a marked 
degree as the result even of slight injuries. 

Owing to the direction of the fibres of the orbicularis, an 
incised wound of the eyelid, if in the vertical direction, will 
gape, while a similar wound in the horizontal direction will 
not do so. Hence the scar left after the former wound is 
apt to be very visible, but that after the latter may be 
almost imperceptible. If the eyelid be divided vertically in 
its entire thickness, unless union by first intention can be 
obtained, a deep furrow is left in the eyelid, and, perhaps, 
at its margin an unsightly coloboma. 

The result of burns of the eyelids has been treated of at 
p. 316. 

Emphysema of the eyelids is sometimes seen after a blow 
on the eye, and is a sign of fracture of the orbit, with a 
communication between the subcutaneous connective tissue 
of the eyelids and the nose, the ethmoid sinus, the frontal 
sinus, or the antrum of Highmore. An emphysematous lid 
is swollen, soft, and crepitating to the touch. 

Ecchymosis of the lower lid, usually with ecchymosis of 
the lower portion of the conjunctiva, after falls or blows on 
the head, is a sign of fracture of the base of the skull, the 
blood making its way along the floor of the orbit. 



CHAP. VIII.] 



THE EYELIDS. 



319 



Simple ecchymosis of the eyelids from blows, commonly 
known as ' black eye,' never gives rise to further compli- 
cation. It requires some fourteen days or more, according to 
the quantity of blood extravasated, before the eye recovers 
its normal appearance. 

Treatment. — Injuries of the eyelids, of whatever kind, are 
of course treated upon general surgical principles. Incised 
wounds should be carefully and neatly drawn together with 
sutures as soon after the injury as possible, and with anti- 
septic precautions. Emphysema may be assisted in its 
absorption by the application of a rather tight bandage, and 
directions should be given to the patient to blow his nose as 
gently as possible, so as to avoid recurrence of the condition. 

"Epicanthus is a congenital deformity, usually binocular, 
which, in the most pronounced cases, consists in partial 
paralysis of the levator palpebral (ptosis) (see chap, xviii.) 
and of the rectus superior, with a narrow palpebral fissure, 
and a fold of integument at the inner canthus concealing the 
caruncle from view, and giving the appearance of great 
breadth to the bridge of the nose. The term is also used for 
cases in which the integumental fold at the inner canthus is 
the only abnormal condition, and this deformity can be some- 
what diminished by the removal of an oval piece of skin from 
the bridge of the nose, its long axis being vertical and its 
width varying according to the effect required. When the 
margins of the wound are brought together the abnormal 
folds are diminished in width. 

Congenital Coloboma of the upper lid — sometimes asso- 
ciated with a dermoid cyst of the limbus of the cornea 
corresponding to the cleft in the lid — and even congenital 
absence of the eyelids, have been occasionally observed. 



CHAPTER IX. 



DISEASES OF THE LACRIMAL ' APPARATUS. 

Malposition of the Punctum Lacrimale. 2 — The punctum 
in the lower lid is more efficient than that in the upper 
lid for carrying off the tears, and a derangement of the 
lower punctum alone is sufficient to give rise to epiphora. 
Inversion of the punctum accompanies entropium of the lower 
eyelid, while eversion of it is present with ectropium of the 
lid. A slight eversion, quite sufficient to cause epiphora, may 
exist without any marked ectropium of the lid, and it is these 
cases which more properly belong to this chapter. They are 
the result generally of some chronic, although it may be 
slight, skin affection of the lower lid, which draws the inner 
end of the latter a little away from the eyeball. 

A prominent symptom of this and of all the following 
lacrimal affections is lacrimation, or epiphora (eVi^opa 
SaKpvcov, a flow of tears), a flowing of tears over the cheek. 

Treatment. — Inversion of the punctum can only be relieved 
by an entropium operation on the eyelid. For the treat- 
ment of eversion of the punctum, see below. 

Stenosis, and Complete Occlusion of the Punctum 

Lacrimale. — Either of these conditions may result from con- 
junctivitis, or from marginal blepharitis, although they may 
not appear for a length of time after those affections have 



1 Laorima, a tear. 

2 la this chapter, and elsewhere in the book, the terms punctum 
lacrimale and canaliculus refer to the inferior passage, unless it be 
otherwise expressly stated. 

320 



chap, ix.] ME LACRIMAL APPARATUS. 



321 



passed away, and the original affection may have 
bsen so slight as to have escaped the observation of 
the patient. In stenosis the size of the punctum 
mav become so extremely minute, that even the 
normal flow of tears is too copious to pass through 
it. Complete occlusion is probably only a more 
advanced stage of stenosis. 

The Treatment, in cases of eversion of the punctum 
where there is no marked ectropium of the lid, 
of stenosis, and of complete occlusion, is similar, 
namely, the opening up of the punctum, and its 
conversion into a slit. This is done with a Weber's 
knife (Fig. 146), the probe-point of which is passed 
into the punctum in cases of eversion, forced into 
the small opening in cases of stenosis, or forced 
through the usually thin covering of the punctum 
in cases of occlusion. In doing this the lower 
lid should be stretched tightly by a finger of 
the surgeon's left hand placed near the external 
canthus. The probe-point having entered the 
punctum, the edge of the knife is turned slightly 
towards the eyeball, and the instrument is pushed 
on into the canaliculus, until 2 mm. of the latter 
has been opened up, and is then withdrawn. If 
the edge of the knife be directed outwards in this 
proceeding, the incision comes to lie on the outer edge ||| 
of the intermarginal portion of the lid, and not in 
contact with the eyeball ; consequently the result is 
unsatisfactory, for the tears are not carried away, 
and moreover the disfigurement produced is con- 
siderable. A slitting up of the whole, or the 
greater part, of the canaliculus in these cases is 
unnecessary, and interferes with the physiological 
action of the tear passage. For two or three days 
after the little operation, it is necessary to pass a probe 



322 



DISEASES OF THE EYE. 



[CHAP. IX. 



daily along the portion of the canaliculus which has been 
slit up, to prevent union taking place. 

When, as sometimes happens in old people, and oc- 
casionally even in the middle-aged, from relaxation of the 
orbicularis the inner end only of the under lid is everted, 
the excision of a small flap of conjunctiva somewhat after 
the manner of Fergus (p. 314) will restore the punctum 
to its normal position. 

Obstruction of the Canaliculus. — The canaliculus may 

be diminished in its calibre, or entirelyclosed, by contraction, 
the result of inflammation which has extended to it from 
the conjunctival sac. It is not possible to diagnose the 
presence of either of these conditions, which may be associated 
witb stenosis or occlusion of the punctum lacrimale, except 
by the introduction of a very fine probe into the canaliculus. 
The passage may also be obstructed by an eyelash, a chalky 
deposit, or a mass of streptothrix. 

The diagnosis of streptothrix in the inferior canaliculus — 
it rarely affects the upper canaliculus — is made by the 
following signs and symptoms : — Lacrimation ; the presence 
of a creamy-yellow discharge at the inner canthus, with- 
out dacryocystitis ; congestion of the caruncle and neigh- 
bouring parts of the conjunctiva. On everting the inner 
end of the lower lid, the region corresponding to the 
canaliculus is seen to be rounded and swollen on its con- 
junctival aspect. The lacrimal punctum is enlarged, stands 
out from the eyeball when the patient looks up, and is filled 
with creamy exudation. On palpation, a hard cylindrical 
mass can be felt in the canaliculus. At a later stage, severe 
purulent inflammation of the canaliculus comes on, with 
marked swelling of the eyelid in the neighbourhood, and pain. 
The gi'eenish-yellow dacryolith contained in the canaliculus 
usually consists of a streptothrix, which some regard as 
actinomyces. 

Treatment. — Where there is merely diminution in the calibre 



CHAP. IX.] 



1 1I E LAt 'RIM. 1 L APPA B A Tt r S. 



323 



of the passage, the introduction of prohes, increasing in size, 
is frequently sufficient to effect a cure. If dilatation fail, 
recourse must be had to slitting up the canaliculus ; but, if 
it can possibly be avoided — that is, if a less extended opening 
will answer — the passage shoidd not be slit up in its entire 
length. At least 3 mm. of its median end ought to be left 
intact, as otherwise regurgitation of tears from the lacrimal 
sac is liable to trouble the patient ever afterwards. If the 
canaliculus be completely closed by adhesions, so that a fine 
probe cannot be pushed through it, it becomes necessary to 
rip it up with the point of any small knife, following the 
known course of the passage from the outside. If the canali- 
culus be closed as far as the opening into the sac, or if 
only at that point, the obstruction must be pierced with 
the point of a fine knife. A difficulty in all these cases 
is to keep the passage patent when once formed. A plan 
which affords tolerable certainty of this is the frequent 
passage of probes into the sac until the tendency to closure 
seems to have ceased ; but even under favourable conditions 
recurrences of the closure are apt to occur. 

.Streptothrix in the lower canaliculus is readily cured by 
slitting up the passage and evacuating its contents. 

Stricture of the Nasal Duct is usually the result of 

simple swelling of its mucous membrane in a catarrhal attack, 
which has originated in the nasal mucous membrane ; or, of 
membranous or cicatricial contraction of the mucous mem- 
brane resulting from long-continued catarrh. It also occurs 
in consequence of disease of the bones of the nose — e.g., in 
syphilis, acquired or congenital, and from blows which fracture 
the bridge of the nose. 

Trmtrmnt. — It is desirable to commence the treatment by 
syringing the nasal duct, the fine point of an Anel's syringe 
being introduced into the punctum lacrirnale and canaliculus. 
By th is means the presence or absence of a stricture is 
ascertained — the fluid, if there be no stricture, passing freely 



321 



DISEASES OF Till-: BYE. 



[chap. ix. 



into the nostril. In some cases, where the obstruction is 
merely a plug of mucus, a cure may at once be effected. 
Stricture due to acute inflammatory swelling of the mucous 
membrane should be treated by the injection of weak alum 
or other astringent solutions into the lacrimal sac, or clown 
the nasal duct, by means of an Anel's syringe, and attention 
should be paid to the nasal mucous membrane. Probing 




Fig. 147. 



here should not be attempted, lest it injure the delicate 
swollen mucous membrane of the duct. 

Membranous or cicatricial strictures are best treated 
by means of probes in the manner proposed by Sir William 
Bowman. The inferior canaliculus is slit up to a slight 
extent so as to admit the point of one of Bowman's smallest 
probes, which is given a curve to suit that of the nasal 
duct. With a finger of the left hand (Fig. 147), if it 
be the patient's left eye, the surgeon stretches the lower 
lid, and, entering the probe with the right hand into the 



CHAP. IX.] 



THE LA C 11 IMA L APPARATUS. 



325 



canaliculus, pushes it gently along its floor until the point 
reaches the lacrimal bone (Fig. 147, position No. 1). The 
point being kept pressed against this bone, the direction of 
the probe is now altered, -by carrying its free end upwards 
towards the bridge of the nose, until its point in the 
lacrimal sac is directed towards, or aimed at, the sulcus 
between the ala of the nose and the cheek. The probe, then, 
in this position (Fig. 147, position No. 2) corresponds to the 
prolonged axis of the nasal duct, down which it is pushed 
slowly and with gentle pressure. If it be the right eye, 
the sui-geon reverses his hands, or operates from behind 
the patient. Any obstacles met with are overcome, if 
possible, by an increase of the pressure ; but if, at any part 
of the passage, much difficulty be encountered, rather than 
that any violence be used, all further manipulation should 
bo postponed to another day ; and it will often be found 
that at the second or third visit the probe is passed with 
comparative ease. Thicker probes are gradually introduced 
at successive sittings, until the largest size has been reached. 

The most common seats for membranous or cicatricial 
stricture of the nasal duct are at its upper end, where it 
enters the sac, and where it is narrowest ; and at its lower 
end, where it is most exposed to catarrhal processes spreading 
from the nostril. 

Should there be reason to think that the stricture is due 
to chronic catarrhal swelling of the lining mucous membrane 
of the duct, astringent injections into the canal, in addition 
to probing, are of use. 

Weber's probes are conical, and of very large calibre at 
their thickest part. The objection to such large probes is 
that when passed into the nasal duct, their thickest part, 
which is 3 to 4 mm. in diameter, corresponds with the upper 
end of the duct, which is its narrowest part, being only 
3 nirn. in diameter. Consequently, the probe becomes more 
or less impacted at this place at each operation, and this 



326 



DISEASES OF THE EYE. 



TCHAP. IX. 



impaction, from injury of the mucous membrane and peri- 
osteum, is liable ultimately to give rise there to hypertrophy 
of the periosteum, and finally to stricture ; so that, while 
the immediate effect of their use is perhaps even brilliant, 
the ultimate result is often the very reverse. When used 
by the inferior canaliculus, their size makes it necessary to 
slit that passage in its entire length, and the entrance of 
the passage into the sac must be enormously dilated by 
so large an instrument, both of which circumstances are most 
undesirable. The same objection applies to the large probes 
introduced by Theobald. Syringing the nasal duct should 
not be performed after passing a probe, lest cellulitis be 
set up. 

To prevent closure of the duct when once made free, 
Mr. Arthur Benson advocates the use of leaden styles, re- 
movable by the patient. He first divides the canaliculus (by 
preference the upper one), and dilates the stricture with 
probes in the ordinary way, and then introduces into the 
duct a piece of leaden wire 1*5 mm. to 2 mm. in diameter, 
cut to length, and smoothed off at the ends. The upper end 
is curved so as to lie out on the cheek. The style is at first 
removed daily, and the duct syringed, until any existing in- 
flammation and discharge have almost ceased. The intervals 
are then increased ; and as soon as practicable the patient 
is taught to remove the style and to replace it himself. When 
he is able to do this easily, he is directed to leave the style 
out for some hours each day, and finally to wear it only at 
night. 

Very obstinate membranous strictures can sometimes be 
freed by electrolysis. 

The most favourable cases of stricture for cure are those 
due to inflammatory swelling of the mucous membrane, and 
next in order come those caused by membranous or cicatricial 
contraction, while those due to bony obstructions must 
be regarded as incurable. 



c-iiap. ix.] THE LACRIMAL APPARATUS. 



327 



Now and then cases of persistent lamination will be met 
with, in which the nasal duct and the rest of the lacrimal 
apparatus are in perfect order. These cases are often due to a 
catarrhal affection of the nasal mucous membrane, slightly 
involving the very lowest extremity of the nasal duct. 
Applications directed towards relief of the nasal affection 
are here indicated. 

Blennorrhcea of the Lacrimal Sac, or Chronic 

Dacryocystitis, is commonly caused, in the first instance, 
by stricture of the nasal duct. In consequence of this 
stricture the tears and the normal mucous secretion of 
the lining membrane of the sac are retained, and offer 
favourable conditions for the growth of micro-organisms, 
of which the pneumococcus is the one usually present. 

But cases of lacrimal blennorrhcea are seen in which 
no stricture of the nasal duct is found. In many of 
these cases there has been a stricture due merely to 
catarrhal swelling of the lining membrane of the duct, 
which has subsided in the course of time without treat- 
ment, and the duct has then again become free, while 
the lacrimal blennorrhcea to which the stricture gave rise 
continues. It is very probable, however, that lacrimal 
blennorrhcea may occasionally come on where there has 
never been a stricture of the nasal duct, and merely as 
an extension of catarrh from the nostrils, especially in 
cases of ozsena, or as an extension of catarrh from the 
conjunctiva. 

Tubercle is occasionally the cause of dacryocystitis, but 
it is not possible to make a clinical diagnosis between these 
and the more common cases, if, as in a few recorded instances, 
the mucous membrane of the lacrimal sac alone be diseased. 
In nearly all cases the tubercular infection of the sac extends 
from the nostril, or from the conjunctiva, one or other of 
which is the primary seat of the disease. 

Sijiii/itomfi. — The patients usually complain of nothing 



:!2S 



DISEASES OF THE EYE. 



[chap, ix . 



more than lacrimation. Those who are more observant of 
themselves may have noticed a swelling, known as a lacri- 
mal tumour or mucocele, in the region of the lacrimal sac ; 
and also that the conjunctival sac, especially when the 
swelling is pressed upon, becomes now and then more or 
less filled with a somewhat thick and opaque discharge, 
which obscures the sight until wiped away. Occasionally 
there is no lacrimal tumour, for the contents of the sac may 
not be copious enough to distend it markedly. 

In order to ascertain in each case of epiphora whether 
or not lacrimal blennorrhcea be present, the surgeon presses 
with his finger over the lacrimal sac, when, if there be 
blennorrhcea, the discharge will be evacuated through the 
puncta into the conjunctival sac. In those cases in which 
there is no longer a stricture of the nasal duct, the discharge 
may pass downwards into the nose, and the patient will feel 
it in his nostril, out of which he can then blow it. 

Conjunctivitis must sometimes be regarded, not as the 
cause, but rather as the effect of a lacrimal blennorrhea, 
by reason of the discharge from the lacrimal sac making its 
way into the conjunctival sac. Blepharitis, too, is seen as 
a further result of irritation from the discharge in old- 
standing cases. 

The most serious complication of chronic dacryocystitis is 
the serpiginous ulcer of the cornea, caiised through infection 
by the pneumococcns (see p. 225). 

Treatment. — It is important, in the first place, to ascertain 
whether there be a stricture of the nasal duct, and for this 
purpose water should be injected by means of an Anel's 
syringe through the canaliculus into the duct. If the fluid 
make its way freely into the nose or phai'ynx, it may be 
taken for granted that the nasal duct is not obstructed ; but 
if, instead of passing through — or only under high pressure 
— it distend the lacrimal tumour to a greater size, a stricture 
may be assumed. If stricture of the nasal duct be present, 



( hap. ix.] THE LACRIMAL APPARATUS. 



329 



it must be relieved, or all other measures will prove futile. 
Should there be no stricture, and also before and after any 
existing stricture has been freed, the treatment consists in 
the very frequent pressing out of the contents of the sac by 
the patient, so that no distension of it may occur : and in 
doing this he should endeavour to cause the discharge to 
pass down the nose rather than into the eye ; while the 
surgeon, having, if necessary, dilated the canaliculus, injects 
astringent solutions into the sac daily, to relieve the catarrh. 
Protargol, in a 15 or 20 per cent, solution, is a useful 
application for introduction into the lacrimal sac. The 
latter should first be washed out with a physiological salt 
solution. Other fluids which have been recommended are 
Sol. Argyrol 25 per cent., Sol. Hydrarg. oxycyanat. 2 per 
cent., Sol. Potas. perman. 1 in 2,500. 

The caustic treatment (recommended further on for acute 
dacryocystitis) is often of the greatest benefit in these chronic 
cases. Any existing conjunctivitis or nasal catarrh should 
be treated. But there are many cases in which no treat- 
ment, short of obliteration or extirpation of the lacrimal sac, 
will bring about a radical cure of this very troublesome 
complaint. 

Obliteration of the sac can be done by the application 
of a galvano-cautery to the lining membrane of the sac, but 
it is a most unsatisfactory proceeding. 

* Extirpation of the lacrimal sac is a far preferable 
proceeding, and for it Kuhnt's method is probably the best. 

Prior to the operation the contents of the sac should be 
expressed, and its cavity washed out with a sterilized salt 
solution. To render the sac more easily found, some 
surgeons fill it out with paraffin prepared for surgical use 
with a melting point of 110°, which is injected with a paraffin 
<>r other syringe through the lower canaliculus. The paraffin 
at once hardens, and the sac becomes outlined. 

It is necessary that the patient should be deeply 



DISEASES OF THE EYE. 



[chap. IX. 



anajsthetised, or an effectual local anaesthesia may be obtained 
as follows : — About ten minutes before the operation a few 
drops of the following solution is injected subcutaneously : 
three drops of a 1 in 1,000 solution of adrenalin, to which 
is added 1 c.cm. of a 1 per cent solution of cocaine. After 
the injection it is necessary to wait until the field of 
operation becomes of a waxy whiteness. The operation 
can then be performed almost painlessly. By this means 
too, the haemorrhage is reduced to a minimum. As a result 
of the injection slight oedema of the region may be seen 
a few days after the operation, and a rather tight bandage 
should be applied, as there may be some hemorrhage when 
the vascular contraction gives way. 

An incision down to the bone and about 2-5 cm. long is 
made over the anterior lacrimal crest. It begins 4 mm. above 
the internal palpebral ligament, and ends 5 mm. below the 
commencement of the bony lacrimal duct. As a rule the 
palpebral ligament is not divided by this incision, and has 
now to be separated with the scissors close to its insertion. 
Miiller's speculum is then inserted to draw aside the lips 
of the wound, and Axenfeld's speculum in inserted from 
the nasal side into the upper and lower angles of the 
wound as deep as the periosteum, to check the troublesome 
haemorrhage which proceeds mainly from those angles 
(Fig. 148). If there be bleeding from the small arteries, 
they are seized and twisted. The fibrous capsule of the sac 
is carefully incised along the crest, care being taken that the 
sac itself is not opened. The anterior wall of the sac, 
greyish blue and shining when no paraffin has been 
injected, then becomes exposed in the cavity. To remove 
the sac the surgeon separates its inner wall from the 
periosteum with the closed blunt ends of the scissors ; then 
the fundus of the sac, along with the strong fibrous 
capsule which is here adherent to it, is drawn forwards, 
and with a few strokes of the scissors is separated from 



nt.vr. ix.] Till: LACRIMAL APPARATUS. 



331 



its bed, and the scissors are passed behind the sac from 
above and the posterior wall similarly separated. The 
fundus of the sac is then drawn inwards and forwards, 
and the outer and what remains attached of the anterior 
surface are made free. Finally, the sac is cut off close 
to the bony canal, and, if there be no close stricture present, 
the mucous membrane of the duct is curetted with a sharp 
spoon. The wound is closed by two or three deeply placed 




sutures, special care being taken to secure the palpebral 
ligament to its insertion. 

Should the sac be opened during the operation, its total 
extirpation will be rendered much more difficult ; and 
if a portion of the sac be left behind, ths object of the 
operation is likely to be frustrated by a return of suppura- 
tion. If the sac be not got out in its entirety, the 
suspicious places must be destroyed by curetting. Where 
there is a fistula of the sac, or where there has been 



332 



DISEASES OF THE EYE. 



[chap. IX. 



phlegmonous dacryocystitis, the operation is rendered diffi- 
cult by reason of adhesions. Some surgeons consider it 
unnecessary and undesirable to divide the palpebral ligament, 
because it is likely to lead to some disfigurement, no matter 
how carefully the sutures may be applied, but this is not 
our experience. The wound heals rapidly by first intention, 
leaving a fine cicatrix which causes practically no dis- 
figurement. 

After extirpation of the "suppurating lacrimal sac, a source 
of danger to the eye has been removed, and the patient has 
been relieved of a troublesome and disfiguring complaint. 
The lacrimation is less after the operation than before it, 
not, as has been stated, because the lacrimal gland undergoes 
atrophy, for no such atrophy takes place, but rather owing 
to elimination of the fifth nerve reflex from the walls of 
the diseased sac and from the inflamed conjunctiva. Indeed, 
unless the surface of the eye be exposed to some considerable 
irritation, e.g. cold wind, foreign body, etc., or there be some 
psychical emotion, the lacrimation is in no way disturbing, 
notwithstanding the complete closure of the lacrimal passage ; 
and an adecpiate explanation of this cannot be offered. Should 
the lacrimation in some instances be troublesome, removal 
of the palpebral portion of the lacrimal gland is indicated 
(p. 337). Removal of the orbital portion of the gland is 
seldom needed, as its functions seem to cease after removal 
of the palpebral glaud, probably owing to closure of its 
ducts consequent on removal of the latter gland. Yet a 
retention tumour of the orbital gland does not ensue. 

Acute Dacryocystitis (SaKpvco, to weep; Kvark, a 
bladder). — Acute inflammation of the lacrimal sac most usually 
comes on when chronic lacrimal blennorrhoca is already 
present. Caries of the nasal bones may cause it, and it 
occurs idiopathically, probably as the result of exposure 
to cold. 

The region of the lacrimal sac and the surrounding integu- 



CHA1MX.] THE LACRIMAL APPARATUS 333 



inent become swollen, tense, and red, and these conditions 
often spread to the lids, giving an appearance which is 
sometimes mistaken for erysipelas ; but the history of the 
case, showing tbe previous existence of lacrimal obstruction, 
etc., will assist the diagnosis. Great pain accompanies tbe 
inflammatory process. Gradually the region corresponding 
to the lacrimal sac becomes the most prominent one of the 
swelling, and the abscess, pointing there, opens. When 
the pus has been discharged the inflammation subsides, and 
the opening through the skin may either close, the parts 
resuming their normal functions, or the opening may remain 
as a permanent fistula. 

The difference between chronic blennorrhcea of the lacrimal 
sac and acute dacryocystitis, besides the fact that one is a 
chronic and the other an acute inflammatory process, is that 
the former process is confined to the mucous membrane of the 
sac, while in the latter the submucous tissue is involved, with 
phlegmonous inflammation as the result. 

Treatment. — In the early stages poultices and purgatives * 
should be employed. As soon as palpation of the sac indicates 
the presence of pus it must be evacuated. This can be effected 
either through the canaliculus, by opening it up to its entrance 
into the sac, or by an incision through the integument over 
tbe sac. The latter is the better method, as it admits of 
free access to the interior of the sac. The next day the 
walls of the sac are to be freely touched with solid mitigated 
nitrate of silver ; or a plug of cotton-wool soaked in a strong 
solution of nitrate of silver may be inserted into its cavity, 
and left there for some hours; or various astringent solutions 
may be injected into the sac. The aim of the treatment, 
whatever it may be, is to secure a rapid return of the 
mucous membrane to its normal condition. If stricture of 
the nasal duct be present, it must be treated pari pccssu. 
By these means the discharge from the sac is arrested, and 
the external opening gradually closes. 



334 



DISEASES OF THE EYE. 



[chap. ix. 



If a fistula should form, it may bo brought to close, in 
many cases, by simply freeing an existing stricture of the 
nasal duct ; or, it may be necessary to pare its edges, and 
bring them together by sutures ; or, especially if there be a 
long fistulous passage, the galvano-cautery, in the form of a 
platinum wire, can be applied with advantage. 

*Dacryoadeilitis (Suicpvoo, to iceep ; ahr/v, a (jland), or 

Inflammation of the Lacrimal Gland — This is a very 

rare affection. It occurs in an acute and in a sub-acute 
form, and is usually symmetrical in each eye. The acute 
form is characterised by swelling of the upper lid, especially 
in its outer third, by chemosis, by diminished mobility of the 
eyeball upwards and outwards, with displacement downwards 
and inwards, by local pain often radiating into the frontal 
region, and by pain on pressure over the gland. On pressure 
too, the tuberous and swollen gland may be felt, unless 
cedema of the lid should interfere. In the sub-acute form 
there is no cedema nor chemosis, and little or no pain, 
and the diagnosis rests on the presence of a hard and 
lobulated mass under the outer third of the upper lid, 
which may displace the globe and interfere with its motion 
upwards and outwards. 

Dacryoadenitis occurs in gonorrhoea, even long after the 
acute stage of the latter is passed, in epidemics of mumps 
with or without parotitis, in influenza, xliphtheria, measles, 
and scarlatina. In all these instances it must be regarded 
as the result of toxic absorption, and having lasted from 
about three to fourteen days it undergoes resolution with 
complete recovery. 

Dacryoadenitis may also be caused, without any con- 
junctivitis, by direct infection with ""the staphylococcus, 
streptococcus, or pneumococcus, each of which have been 
found in the inflammatory products, and these cases are liable 
to go on to suppuration, with formation of abscess. They 
are usually on one side only. 



chap. IX.] TH& LACRIMAL APPARATUS. 



335 



Finally, cases of tubercular dacryoadenitis have been 
recorded. The direct clinical diagnosis of these cases cannot 
be made — the suspicion only of their nature, from the 
presence of tubercular disease in other parts of the system, 
can be raised. 

Treatment. — Treatment of the ordinary toxremia. Locally 
hot fomentations relieve pain and promote resolution. 
When abscess forms, it generally points in the conjunctival 
fornix, and is to be opened there. Should tubercle be 
suspected, removal of the entire gland is indicated. ■ 

^Tumours of the Lacrimal Gland.— Tumours of the 

lacrimal gland are rare. Sarcoma is the most common 
of the new growths here, with its mixed forms fibro-, myxo-, 
adeno-, and lympho-sarcoma. Adenoma is also common, and 
lymphoma, angioma, and some other varieties have been 
observed. In the beginning, the outer third of the upper 
lid seems swollen, but palpation shows this to be caused 
by a tumour behind the lid, not in it, and also that the 
tumour originates in the orbit. Gradually, by pressure 
of this growing tumour, the eyeball becomes displaced 
forwards and inwards, and its motions are curtailed in the 
upward and outward direction. In many instances the 
growth extends backwards into the orbit behind the globe, 
and then the direction of the displacement is more markedly 
forwards. The tumour may become fixed to the orbital 
margin, or the roof of the orbit may be involved and even 
perforated, and vision may be affected, if the optic nerve 
be pressed on. 

Treatment. — Extirpation of the growth is indicated. If 
it come under care at an early stage ; it can be reached 
and effectually removed, either through an incision made 
through the lid parallel to the outer half of the orbital 
margin ; or, the external commissure having been divided, 
and the tipper lid turned up, through an incision made in 
the conjunctival fornix. In later stages, especially when 



33G 



DISEASES OF TJ7E EVE. 



[chap. IX. 



the tumour has extended deeply into the orbit, Kronlein's 
operation (chap, xix.) is indicated. 

*Tubercular Tumour of the Lacrimal Gland. — A few 

cases of tubercular tumour of the lacrimal gland have been 
recorded. The tumour presented itself as a very hard 
mass, about the size of an almond, freely movable under 
the skin, and unattended by pain. In some instances the 
history had extended over several years, and in others has 
lasted for some months only. In most of the cases there was 
tubercular disease elsewhere in the system, but in one instance 
there was none, nor any hereditary disposition to tubercle. 
Treatment. — Exth-pation of the gland. 

*Cysts of the Lacrimal Gland. — These are rare. The 
most common of them is Dacryops, a term applied to a 
retention cyst, which occurs almost exclusively in the 
palpebral portion of the gland, may attain the size of a 
hazel nut, and appears as a more or less transparent bluish 
swelling in the outer part of the upper fornix. 

Treatment. — Excision of a portion of the outer wall of 
the cyst. 

* Symmetrical Chronic Swelling of the Lacrimal 

and Salivary Glands. —A few cases of this remarkable 
affection have been observed. In it there is enormous swel- 
ling of each lacrimal, parotid, and submaxillary gland, while 
the sublingual glands, and small salivary glands in the cheek 
are also swollen, the whole producing a striking alteration 
in the physiognomy of the patient. In one instance partial 
removal of the lacrimal gland was performed, but recur- 
rence took place. 

♦Extirpation of the Lacrimal Gland.— This operation 
is performed by making an incision through the integument 
under the outer third of the orbital margin ; the subjacent 
fascia is dissected up, the gland drawn forward with a 
hook, and dissected out with a scalpel. Or, if it be con- 
sidered sufficient to remove the palpebral portion, this can 



CUAP. IX.] THE LACRIMAL APPARATUS. 



337 



be done from the conjunctival surface, by separating the lids 
widely at the outer canthus, while the patient looks well 



(Kg. 



down and to the nasal side, when the palpebral 
will become prominent in the upper fornix 
and can be seized and cut out 
with scissors. This partial 
removal may be performed for 
persistent lamination when 
other means fail. As already 
stated, when a large tumour 



gland 
149), 



of the "land 



is present, 




Kronlein's operation is often 
needed. The absence of tears, 
which follows upon extirpation 
of the lacrimal gland, is not 
serious for the eye ; for nor- 
mally the gland secretes very p IG j.49 
little, unless under the stimulus 

of a fifth nerve or psychical reflex. Under other conditions, 
the surface of the eye is kept moist mainly by the con- 
junctival secretion, which consists not merely of mucus, 
but of a watery fluid sufficient when there is absolutely 
no secretion of tears — as in extirpation of the lacrimal gland 
combined with paralysis of the fifth nerve — to keep the 
surface of the eye moist. 



22 



CHAPTER X. 



DISEASES OF THE SCLEROTIC. 

Inflammation of the sclerotic is not a common disease, 
although the diagnosis 1 scleritis ' is often made by inex- 
perienced persons, every redness of the white of the eye 
being taken for inflammation of the sclerotic. Beginners are 
warned against this error. Iritis, cyclitis, and sometimes 
conjunctivitis, as well as scleritis, cause redness of the white 
of the eye. 

The diagnosis from conjunctivitis is easily made, by ob- 
serving whether the conjunctival vessels can be moved over 
the affected part or not ; while in iritis and cyclitis the ciliary 
injection is confined to the part immediately, surrounding the 
cornea. Moreover, in iritis the appearance of the iris itself 
is conclusive ; and in scleritis, as will be seen just now, the 
appearances are characteristic. 

Scleritis attacks only that part of the sclerotic which is an- 
terior to the equator of the eyeball, and it is either superficial 
or deep. The superficial form is known as episcleritis. Yet 
it is not always possible to distinguish between these two 
forms in a given case, as the appearances in the early stages 
are very similar. They are probably only different degrees 
of the same disease. But the necessity of admitting the 
existence of two forms depends upon the different course they 
each take ; the superficial form being a relatively harmless 
disease, while the deep form entails serious consequences. 

Episcleritis. — Of this two kinds are recognised :— 
1. Periodic Transient Episcleritis (Fuchs), or Hot Eye 

338 



CHAP. X.] 



THE SCLEROTIC. 



339 



(Hutchinson). It is characterised by frequently recurring 
attacks of inflammation of the episcleral connective tissue, 
giving rise to a vascular injection of a violet hue, but without 
any catarrhal or other secretion, or any hard infiltration, as 
in episcleritis of the usual type. It rarely attacks the whole 
sclerotic at one time, but is commonly confined to a quadrant 
or more, and wanders from one place to another. When the 
attack subsides there is no stain left. The attack may be 
confined to one eye, or it may be in both, or it may affect 
sometimes one eye and sometimes the other. Pain, watering 
of the eye, and photophobia are present in varying degrees. 
Sometimes there is swelling of the eyelids. Occasionally the 
iris and ciliary body become inflamed, and also the cellular 
tissue of the orbit, with resulting exophthalmos. The 
attacks last from one or two days to several weeks, and may 
recur once or twice a year and at intervals of only two or 
three weeks. Patients are usually liable to the disease for 
several years of their life. It attacks adults of middle age 
for the most part. Hutchinson assigns gout as the cause ; 
but Fuchs has not been able to find any symptoms of that 
diathesis in his patients. Rheumatism and malaria seem 
sometimes to produce it, and some observers hold that 
episcleritis and scleritis are frequently of tubercular or 
of syphilitic origin. 

Treatment. — The long continuance of most of the cases 
shows that treatment has but little influence over the disease. 
Quinine and salicylate of soda internally are the remedies 
likely to be of most use, with local warm fomentations, 
momne, and a protection bandage during an attack. 

2. Episcleritis, of the usual type. This appears as 
a circumscribed purplish, rather than red, spot, close 
to, or 2 to 3 mm. removed from, the corneal margin. 
It is often unattended by pain, unless when the eye 
is exposed to irritating causes, and need not be ele- 
vated above the level of the sclerotic ; but in severe 



340 DISEASES OF THE EVE. 



cases there is a decided node at the affected place, with 
more or less pronounced pain, which is increased on pressure. 
All the symptoms disappear in the course of a few weeks, 
and reappear at an adjoining place j and in this way, in 
time, the whole circumference of the sclerotic will have been 
attacked. The duration of the affection is usually lone/ ; 
and, in those instances where the entire sclerotic becomes 
affected by degrees, the process may last for years, on and 
off. Both eyes are often affected. The disease is liable to 
leave behind it a dusky discoloration of the sclerotic where 
each node was seated, but otherwise no harm to the eye 
ensues. But the patient should be made acquainted with 
the tedious nature of the affection. Very mild attacks of 
episcleritis will be met with, which pass away in a few 
days, and do not recur. 

Causes. — The affection is often of gouty or rheumatic 
origin. It occurs sometimes in persons of tubercular or 
syphilitic constitution ; and it is more frequent in senior 
adults than in children or young people, and more com- 
monly attacks women than men. 

Treatment. — No irritant should be applied to the eye. 
Local treatment should be confined to protection with 
dressing and bandages, warm fomentations, and dionine. 
In addition to these, massage should be used, if there be 
not too great tenderness on pressure. Leeching at the 
external canthus is of use when the pain is severe. As 
regards internal remedies, where a syphilitic taint is present, 
mercury should be employed ; if struma, cod-liver oil, maltine, 
etc. ; or if, as is most frequently the case, rheumatism be 
the source of the evil, large doses of salicylate of sodium 
(say 20 grains four times a day) will often be found to act 
well. Salicylate of lithium is recommended in preference 
to the sodium salt by some. Iodide of potassium in large 
doses (20 grains four times a day, or oftener) is a useful 
remedy in some cases of this obstinate disease. 



CHAP. X.] 



341 



Deep Scleritis. — Here the whole of that part of the 
sclerotic which forms the front of the eye is more likely 
to be affected at once than in the milder forms ; although 
cases often enough occur where only an isolated node is 
present at one time.' 

It is the progress of the case alone which can render the 
diagnosis between this and the milder forms certain, and 
hence the importance of a guarded prognosis in the early 
stages of every case of scleritis. In this deep form changes 
— thinning and softening — of the scleral tissue take place, 
which render the latter less resistant, and consequently expose 
it to distension by even the normal intraocular tension. The 
result of this is a bulging (staphyloma) of the anterior 
part of the eyeball. This bulging in itself produces myopia, 
and has a deleterious effect upon the sight ; but, at a later 
period, vision is often wholly destroyed by secondary glaucoma. 
It may happen, that the thinning, etc., of the sclerotic 
affects only a portion, and not the whole, of its anterior 
surface; and in such a case the resulting staphyloma will 
be confined to that part of the sclerotic. A staphyloma, 
whether total or partial, presents a bluish-grey appearance, 
clue to the uveal tract shining through the thinned sclerotic. 

Either with or without such staphylomatous changes, 
sclerotising opacity of the cornea may come on, and iritis, 
chorioiditis, and opacity of the vitreous humour are not 
uncommon complications, especially in strumous subjects. 
Both eyes are usually affected. 

Causes. — Young adults are the most common subjects of 
deep scleritis, and it attacks females more often than males. 
Syphilis, congenital or acquired, rheumatism, gout, tubercle, 
and disturbances of menstruation are the most common 
assignable causes. 

TreaMhenb. — There are few diseases less amenable to 
treatment. When any of the above causes can be assumed 
to be present, the suitable remedies are of course indicated. 



342 



[CUAP. X. 



Besides this, a bandage when only one eye is affected, warm 
fomentations, dionine, dry cupping on the temple, or the 
artificial leech, complete rest of the eyes, and protection with 
dark glasses are to be recommended. 

When all acute inflammation has passed away, an iridectomy 
is sometimes indicated — either for optical purposes, when 
the pupil is obstructed by corneal opacity, or for the pur- 
pose of reducing glaucomatous tension, or of diminishing a 
staphyloma. 

*Syphilitic Gumma of the Sclerotic. — This is rare. 

The diagnosis depends to a great extent on the history 
and co-existing signs of syphilis. The appearance usually 
presented is that of one or more rounded tumours of 
sizes which may vary from that of a pea to that of a 
hazel nut. These tumours are covered with a highly in- 
jected conjunctiva, through which the yellowish colour of 
the gummata shines. They are seated close to the corneal 
margin — and, consequently, give rise to opacity in the 
neighbouring sector of the latter— but may extend as far as 
the equator, or even farther back. As a rule there is much 
pain in the eye and head. Iritis, retinitis, and vitreous 
opacities may form complications. In advanced stages the 
sclerotic may be perforated, or become staphylomatous, 
and the gumma may extend to the interior of the eye, 
producing detachment of the retina, and atrophy of the 
eyeball. 

Treatment.— -In the early stages an energetic mercurial 
treatment is capable of producing such perfect cures that 
not even a slight discoloration of the sclerotic remains. 

*Tubercle of the Sclerotic— Apart from those cases 

of episcleritis and scleritis which may be due to tubercle, the 
only form in which primary tubercle of the sclerotic occurs 
is as a small tubercular abscess or cyst, and such cases 
are rare. In one which occurred at the Victoria Hospital 
the small subconjunctival elevation (Fig. 150) was situated 



CHAP. X.] 



THE SCLEROTIC. 



343 



about 4 mm. from the lower margin of the cornea. It 
was 4 mm. broad at its base, and towards its apex was 
of a pearly white colour, while the vessels of the conjunctiva 
covering it were much injected. The abscess was incised, 
and its cavity in the substance of the sclerotic thoroughly 
curetted, after which a rapid cure took place. Examination 
of the contents of the abscess demonstrated the presence of 
the tubercle bacillus. 

In the majority of cases of tubercle of the sclerotic, 
the disease is an extension from 



the root of the iris, or from the 
ciliary body, where it has had its 
primary seat. Gradually the 
sclerotic becomes thinned by the 
tubercular disease, staphyloma 




forms, and finally rupture may Fig. 150. 

take place. In these cases, if the 

disease be not too advanced, treatment with tuberculin 
T. R. may be tried, but in later stages excision of the 
eyeball is indicated. 

*Tumours of the Sclerotic, as primary growths, are 
exceedingly rare ; but fibroma, sarcoma, and osteoma have 
been so observed. 

*Pigment Spots of a yellowish-brown colour are often 
seen in the sclerotic close to the corneal margin. They 
are congenital, and of no importance. Occasionally a black 
pigmented patch may be associated with pigmented sarcoma 
of the ciliary region. 

Injuries of the Sclerotic. — Ruptures and perforating 
wounds are those which have to be considered. Mere losses 
of substance may be said not to occur. 

The primary danger of a rupture or perforating wound of 
the sclerotic — apart from the loss of the contents of the eyeball, 
which is often associated with it — consists in the possibility 
of infecting organisms being introduced into the interior 



344 



DISEASES OF THE EYE. 



[chap. x. 



of the eye, and there setting up serious inflammatory 
reaction. 

Ruptures are caused by blows on the eye, and are often 
indirect ; thus, if the blow be received below the cornea, the 
rupture may take place above the cornea. A common cause 
of sclerotic ruptures amongst the agricultural population is a 
blow from a cow's horn, while the animal is being tied up or 
fed in the byre. The lower and outer part of the orbit is 
the least prominent, and therefore the eye is least protected 
here, and hence it is commonly driven upwards and inwards 
by the blow, and the sclerotic usually ruptures from 2 mm. 
to 5 mm. from the upper and inner margin of the cornea, 
and concentrically with the latter. Often the conjunctiva is not 
ruptured, but bridges over the opening in the sclerotic. Son\e 
of the contents of the eyeball may have been forced out 
through the rupture — e.g., portions of the uvea, iris, and ciliary 
body, the vitreous, and the lens ; and it is sometimes difficult 
at first to ascertain the exact state of affairs, by reason of 
extravasated blood in the anterior chamber, under the con- 
junctiva, and in the tissues of the eyelids. When the 
conjunctiva is not ruptured, it is often advisable to confine 
treatment to the application of a bandage, as the covering 
conjunctiva acts as a protection against infection of the 
wound. Where serious damage has not been done to the 
retina, fair or even good vision may be regained in many of 
these cases, which at first sight seem almost hopeless ; and, 
should perception of light be present, one may reasonably 
conclude that the retina is not detached. When the lens lias 
been dislocated under the conjunctiva , — from whence it can be 
removed, after the sclerotic opening has closed, — the patient 
will of course require a glass as after cataract operation, to 
give him the best vision. 

A large and gaping perforating wound is easily recognised. 
A portion of the chorioid, ciliary body, or iris, according to 
the position of the wound, probably lies in it, or part of 



CHAP. X.] 



THE SCLEROTIC. 



345 



the vitreous humour may be found iu it ; while the vitreous 
humour, as seen through the pupil, will be full of blood 
(luemophthalmos), and blood may be present in the anterior 
chamber (hyphema, viro, under ; ai\ia, blood), especially if 
the wound be far forwards. Small wounds may be concealed 
by sub-conjunctival haemorrhage, and here reduced tension 
of the eyeball is sometimes a valuable diagnostic sign. 

A clean-cut perforating wound of the sclerotic may heal 
without inflammatory reaction, even when portions of the 
uveal tract or vitreous humour are prolapsed into it, these 
prolapsed parts becoming incarcerated in the cicatrix. 

When inflammatory reaction follows upon one of these 
injuries it may be either of the purulent or plastic form. 
In the former case all the contents of the eyeball take part 
in the suppuration, and we term it panophthalmitis, phthisis 
bulbi being its ultimate result. In the plastic form, the iris 
and ciliary body alone are implicated, and sight is slowly lost ; 
the eye here, too, becoming phthisical. Of the two, the latter 
process is the more serious, as it is prone to give rise to 
sympathetic ophthalmitis — a danger which is not associated 
with the eye lost through panophthalmitis. 

Where the wound has been produced by a small foreign 
body, which has remained in the interior of the eye, the 
position is much more serious, and this subject will be dis- 
cussed in chap. xv. 

Treatment. — In cases where the wound is small (say less 
than 3 mm.), no suture need be used : a carefully applied 
dressing and bandage will be sufficient to promote the natural 
tendency to healing. But, where the wound is large and 
gaping, any prolapsed chorioid, etc., must be freely irrigated 
with sublimate lotion, 1 in 5000, and completely reduced — or 
if the prolapsed parts, or portion of them, cannot be reduced, 
they must be abscised — and the margins cf the wound drawn 
together Ly a few points of fine silk suture passed through 
part of the thickness of the sclerotic ; or, the sutures may be 



34G 



DISEASES OF TEE EYE. 



[chap. x. 



! 



passed through the conjunctiva at some distance from the 
edges of the wound, the traction on the conjunctiva being 
often sufficient to close the scleral wound. A bandage is 
applied to each eye, and the patient is confined to bed. But, 
if tbe injury be such — very gaping wound, much loss of con- 
tents of the eyeball, or extensive intraocular haemorrhage — 
as to render restoration of useful sight, or at least retention 
of the shape of the eyeball, beyond reasonable hope, it is 
wiser to remove the eyeball at once, rather than to run 
tbe risk of sympathetic ophthalmitis without compensating 
advantage. 



CHAPTER XL 
DISEASES OF THE UVEAL TRACT. 

Inflammations. 

The iris, ciliary body, and chorioid 1 together form the uveal 
tract. If it be remembered that they closely resemble each 
other histologically, that their blood supply is identical, and 
that they form with each other a continuous membrane, it is 
a matter of surprise that any one of these three divisions of 
the uveal tract can undergo inflammation while the others 
remain healthy. Yet this is by no means uncommonly the 
case. But it is more common for at least two of them, and 
especially the iris and ciliary body (irido-cyclitis), to be simul- 
taneously inflamed ; and the entire uveal tract may be affected 
at one time (irido-chorioiditis — by which term it is implied, not 
only that the iris and the chorioid are diseased, but also the 
intervening portion of the tract, the ciliary body). If all 
three portions be affected, one of them may be much more 
affected than either of the others. Or, commencing in one 
portion, the inflammatory process often spreads to one or 
both of the other portions. 

Clinically we cannot always know whether only one or 
more than one division of the uveal tract is in a state of 
inflammation. This uncertainty of diagnosis is particularly 
liable to arise when there is severe acute iritis ; for then the 
symptoms present might all be derived from the inflammation 



X<5/> t0 ") the chorion ; hence chorioid, like the chorion. 
347 



348 



DISEASES OF THE EYE. 



[chap. XI. 



of the iris alone, while the contracted and obscured pupil, 
opacity in the aqueous humour and cornea, and irritability 
of the eye, render impossible a diagnosis of chorioiditis by 
the ophthalmoscope ; and, whether in health or disease, the 
position of the ciliary body puts it always out of reach of 
ophthalmoscopic examination. Yet it may be taken for 
granted, that in every rather severe case of iritis, particularly 
in those of syphilitic origin, more or less cyclitis is also 
present ; while a deep anterior chamber, diminished tension, 
tenderness on pressure, or punctate deposits on the posterior 
surface of the cornea increase the suspicion. In most cases 
of very slight iritis there is probably no cyclitis. 

It is only after the acute inflammatory symptoms have 
subsided, and the pupil has become clear, that disseminated 
changes in the chorioid, opacities in the vitreous humour, 
and even retinitis and optic neuritis, which may lead to 
optic atrophy, can be discovered, with their corresponding 
depreciation of vision. 

It is convenient, in a systematic consideration of inflamma- 
tion of the uveal tract, to discuss it under the separate 
headings of iritis, cyclitis, and chorioiditis. 

Inflammation of the Iris. Iritis.— Iritis is acute or 

chronic, the acute cases forming the large majority. Again, 
iritis is primary or secondary. In primary iritis, the iris 
is the original seat of the disease, and is not a result of 
some other diseased process in the eye. In secondary iritis, 
the inflammation has been caused by disease of the cornea 
or sclerotic, or is the result of swelling of an injured lens, 
the presence of an intraocular tumour, etc. 

Acute Iritis.— The Objective Signs of Acute Primary Iritis, 
more or less marked according to the severity of the case, 
are : — (a) loss of lustre and of distinctness of pattern of the 
iris ; (b) change in colour of the iris ; (c) functional disturb- 
ances (impaired mobility) of the iris ; (d) contraction of the 
pupil ; (e) circumcorneal injection of the ciliary vessels. 



CHAP. XI.] 



THE UVEAL TRACT. 



349 



(a) The loss of lustre and of distinctness of pattern is due 
to au alteration in the endothelium, which covers the surface 
of the iris, to the presence of lymph in the iris and on it, 
aud to cloudiness of the aqueous humour through which it 
is seen, caused by inflammatory products held in suspension, 
aud often, also, to some cloudiness of the cornea, (ft) The 
change in colour is due to hyperemia of the iris, as well 
as to the presence of the inflammatory products ; a blue iris 
becomes greenish, a brown iris yellowish, (c) The impaired 
mobility, and the (cZ) contracted pupil, are due £o hyperemia, 
to spasm of the sphincter iridis, and to posterior synechias 
(e) The circumcorneal, or ciliary, injection is due to engorge- 
ment of the episcleral branches of tbe anterior ciliary 
arteries which supply the iris. 

Exudation of inflammatory products is present, in greater 
or less degree, on either surface of the iris, and in its 
stroma ; in the pupil, or rather on the anterior capsule of 
the lens in the pupillary area of the latter, and — when 
as so often happens, cyclitis is associated with iritis — in 
the aqueous humour, and on the posterior surface of the 
cornea. As a consequence of the exudation in and on 
the iris, in addition to change in colour, and loss of pattern, 
the iris is often swollen. 

Posterior synechia? 1 — i.e. adhesions between the iris and 
the anterior capsule of the lens — occur as a result of 
inflammatory exudation on the posterior surface of the iris, 
or on its pupillary margin. The presence of posterior 
synechia? is ascertained by observing the play of the pupil 
when the eye is placed alternately in strong light and in 
deep shadow, or by observing the effect of a drop of atropine 
solution on the pupil, the latter dilating only at those 
places where there are no synechia?. The pupillary margin 
may be adherent at one or two points only, or there may 



avvixw, to bind together. 



350 



DISEASES OF THE EYE. 



[chap. XI. 



be broad synechia) occupying at least a fourth, or a third, 
or more of the margin of the pupil, or there may be both 
small and broad synechia} present, or, finally, the entire 
margin of the pupil may be adherent. If the entire 
pupillary margin have become adherent, the condition is 
termed complete posterior synechia? (or circular posterior 
synechia, ring synechia?, or exclusion of the pupil) ; and 
in such cases, especially if of some standing, atropine has 
no effect on the pupil. When complete posterior synechia 
has developed, the iris after a time becomes bulged forwards 
like the sail of a ship in the wind, by reason of accumulation 
behind it of aqueous humour, which now cannot escape 
into the anterior chamber, and this condition is known 
as iris bombe : it is very liable to cause high tension of 
the eye (Secondary Glaucoma). 

If the area of the pupil be filled with exudation — lying 
on the anterior capsule of the lens — circular synechia being 
usually also present, the condition is known as occlusion of 
the pupil. 

Total posterior synechia is that condition in which the 
whole posterior surface of the iris is adherent to the capsule 
of the lens. It is rarely the result of ordinary iritis, but 
is seen frequently in sympathetic ophthalmitis (p. 380). 

Exudation of inflammatory products into the anterior 
chamber causes turbidity of the aqueous humour, and some- 
times these products sink to the bottom of the chamber 
and form a pseudo-hypopion. In some rare cases, the 
exudation in the anterior chamber takes the form of a 
jelly-like mass, which may resemble a dislocated crystalline 
lens. On the posterior surface of the cornea, in some 
instances, exudation is seen as punctate deposits (so-called 
keratitis punctata), and these, and turbidity of the aqueous 
humour, indicate that the ciliary processes are involved 
in the inflammation. 

The Subjective Symptoms of Acute Primary Iritis are : — 



chap, xi.] 



THE UVEAL TRACT. 



351 



(a) pain, (b) lacriination and photophobia, (c) and dimness of 
vision. («) The pain is due to irritation of the ciliary nerves 
in the inflamed part. Yet this pain is not always so much 
in the eye itself, as in the brow over it, in the corresponding 
side of the nose, and in the malar bone, and may extend to 
the whole side of the head. It varies in its intensity and is 
often more severe at night. Some forms of iritis are 
usually attended by much pain, while others are free from 
it. (6) The lacrimation and photophobia are reflex effects 
from irritation of the fifth nerve, they are often absent, 
and are rarely present to such a degree as in some corneal 
affections, (c) The dimness of vision is due to one or other 
or to all of the following : — turbidity of the aqueous humour, 
punctate deposits on the posterior surface of the cornea, 
exudation of lymph on the pupillary area of the anterior 
capsule of the lens, opacities in the vitreous humour. 

A grave mistake into which beginners often fall is to take a 
case of iritis to be one of conjunctivitis or scleritis (see pp. 132 
and 338), the " redness of the white of the eye " being 
that which misleads. The appearance of the iris itself — 
norma], or exhibiting the signs of iritis — will chiefly assist 
in the diagnosis. Moreover, the pain in iritis is of neuralgic 
character, but in conjunctivitis, if there be any pain, it is 
similar to that caused by a foreign body in the conjunctival 
sac. In iritis there is no discharge, while in conjunctivitis 
the eyelids are gummed in the morning by muco-purulent 
secretion. The vascular in jection in iritis is of the pericorneal 
ciliary vessels, but in conjunctivitis of the conjunctival vessels. 
In iritis, however, it often happens that there is conjunctival 
as well as ciliary injection. But, as stated, in tho diagnosis 
of iritis, the appearance of the iris itself is the most valuable 
guide. Look at the iris. If the opposite eye be healthy, 
compare the iris in the affected eye with that in the healthy 
eye. These latter are the most important precepts in the 
diagnosis of iritis. 



352 



Etioloyy of Acute Primary Iritis. — By far the most common 
cause of acute primary iritis is syphilis, probably 50 per 
cent, of the cases being due to it. Other causes are tubercle, 
rheumatism, gonorrhoea, diabetes, enteric fever, pneumonia, 
influenza. 

Syphilitic Iritis. — It is usually in the secondary stage of 
acquired syphilis, along with, or following on, the papular 
skin eruption, that one sees iritis ; and, in the majority of 
cases, there is no characteristic appearance to indicate 
its specific nature, this diagnosis depending upon the general 
history, or on the presence of other signs of syphilis. The 
plastic inflammatory exudation is present mainly on the 
surface of the iris, and along the pupillary margin, and 
often also in the pupil. The loss of lustre and of distinct- 
ness of pattern are well marked, and there is considerable 
change in colour. Posterior synechias always form, and it 
is occasionally in these cases, that the gelatinous exudation 
in the anterior chambers mentioned above is seen. The 
circumcorneal injection is generally well marked, sometimes 
causing elevation of the limbus of the conjunctiva, and even 
general, although slight, chemosis. The degree of irritation 
(pain, photophobia, and lacrimation) varies considerably, 
and is often slight, even where the appearances in the iris 
are well marked. 

Late in the secondary stage of syphilis, or within a 
year or so after the primary infection, a form of iritis may 
occur which can be recognised as syphilitic. It is charac- 
terised by the formation of circumscribed nodules, or small 
condylomata, of a yellowish-red colour, the rest of the iris 
being apparently intact. These nodules vary in size from 
that of a hemp-seed to that of a small pea, and are situ- 
ated usually at the pupillary margin, occasionally at the 
periphery of the iris, and very rarely in the body of the iris. 
There may be but one nodule present, and there are seldom 
more than three or four. This form is not common. 



CHAP. XI.] 



THE UVEAL TRACT. 



353 



Occasionally iritis occurs in the tertiary stage of syphilis, 
and then sometimes with the formation of inflammatory 
tumours in the iris, which are to be regarded as 
cuinmata. 

In inherited syphilis, iritis does sometimes occur without 
interstitial keratitis (see p. 243), but is more frequently seen 
in conjunction with the latter. Childhood and youth are 
the periods of life in which it is observed. 

Tubercular Iritis. — Next to syphilis, tubercle is probably 
the most common cause of iritis. Tubercle occurs in the 
iris in three forms ; of these, one, the conglomerate or 
solitary tubercle of the iris, will be described under the 
heading of New Growths of the Iris (p. 400). It is not 
usually associated with iritis. The other forms are properly 
regarded as tubercular iritis. They are : — 

a. Very fine miliary nodules which occur in the iris, 
chiefly at the angle of the anterior chamber, or near the 
pupillary margin, where they give rise to posterior synechia?. 
They are of a yellowish -grey colour, or, by reason of vessels 
which may form in them, they may be reddish, or cinnamon 
coloured. There is some iritis, and often, also, punctate de- 
posits on the back of the cornea indicating engagement of the 
ciliary body. The process runs a sluggish course, and is not 
painful ; the nodules increase in size slowly, cease growth, 
become smaller, and finally disappear. This form of 
tubercular iritis has been termed by Leber attenuated 
tuberculosis of the iris, and its prognosis is favourable, 
although some derangement of sight may remain as a result 
of the iritis. The disease is often binocular. 

b. The second, and more common, form of disseminated 
tuberculosis of the iris is also associated with iritis, ac- 
companied with much ciliary injection. But in this form, 
along with small nodules there are some of larger size — 
so large, sometimes, as to touch the back of the cornea. 
Thf;y are of a pale buff colour, and may be scattered over 

23 



354 



DISEASES OF THE EYE. 



[chap. XI. 



the whole iris, although their seat of election — a rather 
important point for the diagnosis — is the angle of the 
anterior chamber. This form is frequently, and in our 
experience at the Victoria Hospital commonly, associated 
with tubercular disease of the true cornea (tubercular kerato- 
iritis), which is manifested by a diffuse haze in the deep 
layers of the cornea, and by the presence, in the same 
layers, of scattered small and large greyish-yellow tubercular 
infiltrations, each of them surrounded by a less intense 
halo. A vascular network, derived from the deep marginal 
vessels, forms about these corneal infiltrations. Punctate 
deposits are present on the back of the cornea, and the 
aqueous humour may be hazy, and if the vitreous humour 
can be examined, it, too, may be found more or less opaque. 
This form usually goes on to complete loss of sight if 
untreated. At a late period, the growth of tubercle ceases, 
and the shape of the eyeball, with more or less opaque 
cornea, may be retained, or caseation followed by phthisis 
bulbi may result. One or both eyes may be attacked. Pain 
is not a prominent symptom — in many cases there is none. 

The diagnosis of tuberculosis of the iris cannot be made 
off-hand from the presence of nodules in the iris, as nodules 
occur in other forms of iritis, notably in syphilitic iritis. 
The syphilitic condyloma is of a yellowish-red, while the 
tubercular nodule is of a greyish-red or of a buff colour, 
and often presents a somewhat translucent appearance. 
Those cases of nodular iritis which are accompanied by 
infiltrations in the deep layers of the cornea, as above 
described, can be regarded with great certainty as tubercular. 
But the history of the patient — exclusion of syphilis acquired 
or congenital — his present state as regards tubercle else- 
where in the system, and the family history as to tubercle 
must be investigated. As tubercle of the iris commonly 
occurs in childhood or in early youth, the exclusion of 
acquired syphilis is not often difficult, and the presence 



CHAP. XI.] 



THE UVEAL TRACT. 



355 



or absence of the stigmata of congenital syphilis decides 
the diagnosis in that respect. In leucaemia, and in pseudo- 
leucceniia, iritis with formation of nodules occurs, and in 
ophthalmia nodosa (p. 176). 

Signs of former or existing tubercular disease elsewhere 
in the body are obviously of great value for the diagnosis, for 
intra-ocular tuberculosis is now held to be always a secondary 
or metastatic condition, the primary focus being elsewhere 
in the system. Should no such focus be found, it must 
be remembered that it is possible for a small tubercular 
deposit to be present in the body, which may cause no 
symptom, and which may escape detection by physical 
examination ; in short, intra-ocular tuberculosis, although 
not the primary focus, may be the first indication of tuber- 
cular infection. 

The macroscopic examination of a portion of the iris 
removed by iridectomy is conclusive for the diagnosis if 
tubercle bacilli can be found in it, but this is rarely 
so. An inoculation experiment, by the insertion of a portion 
of the iris into the anterior chamber of a rabbit's eye, 
gives a more certain result. Neither of these measures, 
however, is admissible, as iridectomy is liable to cause the 
iritis to take on renewed activity. 

Gourfein has proposed, and successfully practised, drawing 
off the aqueous humour from the tuberculous eye with a 
fine hypodermic syringe, and injection of it into the anterior 
chamber of a rabbit's eye, where it gives rise to tubercular 
iritis. This proceeding is harmless. 

Finally, for diagnostic purposes a hypodermic injection 
of tuberculin may be used. Of the old tuberculin a dose 
of 1 m.gr. of the dry substance is injected. If the disease 
be tubercular, a sudden rise of temperature takes places, and 
as rapidly subsides ; and occasionally there is a passing 
local reaction in the eye. 

Rheumatic Iritis is usually of the form which is common 



356 



DISEASES OF THE EYE. 



[ciiAr. xi. 



in the early secondary stage of syphilis (see above), but 
accompanied by circumcorneal injection, which is great in 
proportion to the other signs of iris present. The pain 
is often peculiarly severe, and again the attack may be pain- 
less. Iritis is not found in association with acute rheumatic 
arthritis, but rather with the sub-acute articular rheumatism 
which attacks now one joint and again another through 
several months of the year, in the winter and spring. 
Rheumatic iritis is very liable to recur. 

Gonorrhcoal Iritis is also of this form, but punctate 
deposits on the posterior surface of the cornea are more 
common in it. It does not attend on, nor immediately 
follow, a gonorrho3a ; but an attack of gonorrheal arthritis, 
usually of the knees, always intervenes. It is not very 
common. 

Chronic Iritis. — -Practically the only objective sign of a 
slight case of chronic iritis is posterior synechias with, it may 
be, some slight pupillary exudation. Or, in addition to 
posterior synechias, there may be punctate deposits. Or, 
the latter may be present without synechia, when the case 
is to be regarded rather as chronic cyclitis. Chronic iritis 
with punctate deposits used to be known as serous iritis, 
a term now abandoned. In the severer cases, the stroma 
of the iris is distinctly altered as regards colour and pattern, 
there are abundant deposits on the back of the cornea, and 
opacities in the vitreous humour. There is no pericorneal 
injection in chronic iritis, or, at most, it is slight, occasional, 
and ephemeral. 

The only subjective symptom in chronic iritis is defective 
vision, and this it is which brings the patient for advice. 
There is little or no pain, photophobia, or lamination. On 
examination signs of iritis are found, and inquiry elicits the 
fact that, except for gradual failure of sight, the patient 
has had little trouble beyond an occasional "cold" in the 
e ye — i -e . slight ciliary injection — which lasted a few 



CHAP. XI.] 



THE UVEAL TRACT. 



357 



hours, or a day or so at a time in the course of preceding 
years. 

The slighter cases of this affection which are confined 
to the iris, and do not run a long course, may not cause 
serious loss of sight. The more severe cases, accompanied 
by cyclitis and punctate deposits, are liable to be complicated 
with high tension (secondary glaucoma), owing to blocking 
of the angle of the anterior chamber with exudation, which 
seriously endangers vision. In the severest cases the whole 
uveal tract is involved (chronic irido-chorioiditis) and the 
exudation of inflammatory products is very great, with the 
following results — marked punctate deposits, giving rise to 
parenchymatous opacity of the cornea, turbid aqueous, 
atrophy of the iris, posterior synechia? going on to exclusion 
of the pupil, often occlusion of the pupil, iris bombe, opacity 
of the vitreous humour, cataract, atrophy of the chorioid 
and retina, high tension owing to iris bombe, absolute blind- 
ness, staphyloma of the globe — or in the last stages the eye 
may become phthisical instead of staphylomatous. In some 
few cases iris bombe may not come on, and complete blindness 
may not result, rendering the prospect of a cataract extrac- 
tion fairly good. 

Chronic iritis frequently occurs, or rather commences, 
in youth, and is more common amongst females than males. 
The severe cases may continue intermittently for many years 
before complete blindness is reached. It is often impossible 
to assign a cause for the disease. The patients are usually 
neither syphilitic nor tuberculous. They are sometimes 
delicate and ill-nourished, and the view is held that many 
cases axe due to auto intoxication from the gastro-intestinal 
tract. 

Treatment of Acute Primary Iritis. — A mydriatic (see 
tn hie, p. 420) is in all cases the most important means. 
Host commonly a solution of atropine (Atrop. sulph. gr. iv, 
Aq. desk ^j) is used as eye-drops. An atom of sulphate of 



358 



DISEASES OF THE EYE. 



[chap. XI. 



atropine in substance, placed in the conjunctival sac, gives a 
very active reaction. It is also used in the form of ointment 
(Atrop. sulph. gr. iv, vaselin and gelatine discs containing 
atropine are manufactured. By paralysing the sphincter 
iridis, atropine provides rest for the inflamed iris ; and, if 
adhesions have already formed, the dilatation of the pupil 
may break them down, while if none be as yet present, the 
dilatation will greatly aid in preventing their formation. 
Again, owing to diminished volume of the iris, its vessels 
contain less blood, and the hypersemia, of the inflamed part 
is reduced. Yet in cases of irido-cyclitis, where the cyclitis 
is the prominent factor, atropine does not always promote the 
cure, for by depleting the vessels of the iris it engorges those 
of the ciliary body. To produce a maximum effect on the pupil, 
where it is desired to break down adhesions, six drops of the 
atropine solution should be instilled into the eye, with an 
interval of from five to ten minutes between each ; and in 
this way the atropine from each dmp has time to make its 
way into the anterior chamber, and finally the accumulated 
effect of all six is obtained. More than one drop can hardly 
be retained in the conjunctival sac at a time. The use of 
cocaine (2 per cent.) along with atropine ensures a maximum 
dilatation. A drop of the atropine solution into the eye 
from once or twice to four times a day is required, in 
order to maintain the desired dilatation of the pupil ad 
maximum, in a severe case. 

Some individuals are peculiarly susceptible to atropine 
poisoning, of which the symptoms are : — dryness of the 
throat, fever, fulness in the head, headache, delirium, coma. 
The antidote is morphia, of which £ grain used hypoder- 
mically neutralises -J s grain of atropine in the system. 
Atropine poisoning can occur by the introduction of the 
solution into the stomach through the lacrimal canaliculi, 
nose, and fauces ; and to prevent this the finger of the 
patient may be placed in the inner canthus, so as to occlude 



CHAP. XI.] 



Till: UVEAL TIIACT. 



359 



both canaliculi during, .and for some moments after, the 
introduction of the drop into the eye. 

After use of atropine in some persons the skin of the lower 
evelid, or of both eyelids, becomes eczematous, red, swollen, 
and painful, from infiltration with the drug ; and in other 
cases after long use follicular conjunctivitis is induced. If 
these complications occur, sol. extr. belladonna} (gr. viij ad 
jj) should be substituted for atropine, and suitable remedies 
used for skin (p. 276) or conjunctiva. 

In old people tenesmus and retention of urine sometimes 
result from use of atropine. 

Atropine, while it is so useful a means in the treatment of 
inflammations of the iris, ciliary body, and cornea, is of no 
benefit in many other diseases of the eye, and is positively 
harmful in some of them. It is necessary to make this 
statement very explicitly, for many medical men, who have 
not devoted attention to the subject of eye-disease, include 
atropine in every eye-lotion they prescribe. If the disease 
prescribed for be conjunctivitis, as it very often is, the 
atropine is calculated rather to increase than to relieve the 
conjunctival affection ; while, if the patient be advanced in 
life, there is always the danger that a tendency to glaucoma 
may be present, and in such a case the dilatation of the 
pupil caused by the atropine will be sufficient to bring on 
an attack of acute glaucoma. It falls to the lot of most 
ophthalmic surgeons to be called, at one time or another, to 
a case of acute glaucoma brought on by the use of atropine 
in this thoughtless manner. 

iJark protection spectacles should be worn by patients 
Buffering from iritis; and in severe cases, especially in cold 
weather, a bandage ought to be worn, and the patients 
should be confined to a dark room, and even to bed. 

Hot fomentations — for twenty minutes every two hours — 
are of benefit in all forms of iritis, and relieve pain. Dionino 
is useful also in relieving pain, and seems to promote the 



3G0 



DISEASES OF THE EYE. 



[chap. XT, 



cure. If the pain be severe at night a hypodermic injec- 
tion of morphia may be given. If there be much irritation, 
pericorneal injection, or chemosis, leeching at the external 
canthus over the orbital margin is of use. Occasional 
gentle purgatives are desirable. Blistering on the temples, 
or behind the ear, has been a favourite item in the treat- 
ment of iritis. It adds to the annoyance of the patient, 
but as a remedy is of no value. 

In addition to the foregoing measures which are applicable 
in all cases, the special etiological moment must be con- 
sidered in the treatment of each case, as follows : — 

Treatment of Syphilitic Iritis. — As it is important to 
obtain rapid absorption of the inflammatory products so 
abundantly thrown out, and which would soon cause 
extensive damage to sight, the system should be put under 
the influence of mercury as quickly as possible, by the 
use of mercurial inunctions, or by small doses of calomel 
internally, or by intramuscular injections, 1 grain of metallic 
mercury being injected once or twice a week in the form 
of a cream made with lanolin as recommended by Lambkin. 
When the acute symptoms have passed away, an after treat- 
ment with iodide of potassium should be employed. 1 In 
iritis due to congenital syphilis, mercury is not generally 
indicated, but the syrup of the iodide of iron, and a general 
tonic treatment is preferable. As, in cases of acquired 
syphilis, there is a marked tendency of iritis to relapse, 
it is important that, for some weeks after the acute stage 
has passed, the pupil should be kept under the influence 
of atropine, the eyes protected with dark glasses, and the 
internal administration of iodide of potassium continued. 

An attack of syphilitic iritis may last from two to eight 
weeks, and cases which seem to be slight— i.e., where the 

1 Iodide of potassium must not be prescribed in conjunction with 
treatment by injections of metallic mercury. 



CHAP. XI.] 



Till: UVEAL TRACT. 



3G1 



pupil dilates well and rapidly to atropine, and where but 
little lymph is thrown out— sometimes cause disappoint- 
ment by their slow recovery. It is possible that an attack 
of iritis, if carefully treated from the beginning, may 
leave the eye in as healthy a condition as before, but it 
is more common, in spite of every effort, to find isolated 
posterior synechia?, or a circular synechia, left behind. 
The presence of a few isolated synechia?, if the pupil be 
clear, is in itself harmless to sight ; but, if relapse should 
take place, and fresh adhesions form, a complete posterior 
synechia (see p. 350) going on to iris bombe may ulti- 
mately be established. Complete posterior synechia may 
of course result from the first and only attack of iritis. 

In some cases of iritis, the vitreous humour becomes more 
or less opaque, and this condition does not always disappear 
as the iritis gets well ; indeed, it may not be possible to ascer- 
tain its presence until after the inflammatory process in the 
iris has subsided. In these cases the ciliary body has 
participated in the inflammation, although there may have 
been no punctate deposits on the cornea. Again, there 
may have been some chorioiditis and retinitis during the 
attack. Great and permanent deterioration of vision may 
result from such complications ; and this emphasises the 
importance of a cautious prognosis at the commencement. 

In complete posterior synechia, after the acute iritis has 
subsided, an iridectomy (p. 411) is indicated to restore 
communication between the posterior and anterior chambers. 
For the treatment of opacities in the vitreous humour see 
chap, xv., and of syphilitic chorioiditis see chap. xvi. 

Treatment of Tubercular Iritis. — Cases of attenuated 
tuberculosis of the iris simply require local treatment with 
atropine, hot fomentations, and protection spectacles. In 
the treatment of the more pronounced form of tubercular 
iritis, the tubercular infection must be combated, and the 
chief therapeutic measure which is of value for this purpose 



362 



DISEASES OE THE EYE. 



[CHAP. XI. 



is inoculation with the new tuberculin. The method at 
first used at the Victoria Hospital was that laid down 
by A. von Hippel, who introduced treatment with tuberculin 
into ophthalmic practice. It is as follows : — During the 
entire course of treatment von Hippel recommends the 
temperature to be taken every two hours. The subcutaneous, 
or intramuscular, injections are made every second day. 
They commence with a dose of -g^ mg. of the dry substance, 
and each successive dose is increased by ¥ £ ff mg. until ^ mg. 
is reached. Each dose is then increased by T \ mg. until 
i§ mg. is reached, then by mg. and so on, the highest 
dose given in any case being 1 mg. But if, after a dose has 
been given, a rise of temperature of over 38° 0. take place, the 
previous dose is repeated, and a further increase is not made 
until a general reaction ceases to be caused. In the majority 
of cases treated, marked improvement became apparent within 
a few weeks, the nodules in the iris becoming smaller and 
less vascularised, the deep-seated corneal infiltrations thinner, 
the punctate deposits fewer, and the eye less irritable and 
injected, until finally, with continued treatment, all tuber- 
cular deposits and infection disappeared, leaving only such 
permanent damage to the eye and sight — due to corneal 
changes and pupillary occasion — as may be proportional to 
the duration and severity of the disease before treatment 
took effect. The treatment is a protracted one, as long as 
six months, possibly, being needed to effect cure in a severe 
case. 

In the light of the investigations of Sir A. E. Wright, we 
now use doses of only xoVii *° inro m §- °f tuberculin T.R., 
which do not raise the temperature, and the dose is not 
repeated until the opsonic index shows that the effect of 
the preceding inoculation is passing off". Valuable adjuncts 
in the treatment with tuberculin are local hot fomentations, 
or the Japanese warmer, with the administration internally 
of citric acid — a decalcifying agent, to reduce the coagulability 



CHAP. XI.] 



THE UVEAL TRACT. 



363 



and viscidity of the blood — cod liver oil, and syrup of the 
iodide of iron. 

On the question as to whether an eye which is disorganised 
by intraocular tuberculosis beyond hope of recovery should 
be excised, opinions are divided. Were the eye the primary 
focus, excision might be indicated in even a less advanced 
stage. But cases are on record in which, soon after excision 
of a tubercular eyeball, death from tubercular meningitis, 
or from acute miliary tuberculosis, took place ; and which 
were therefore suggestive of dissemination of the tubercle as 
direct result of the operation. We can offer no experience 
of our own in this connection, but it would seem that there 
is a risk in removing the eyeball in these cases. Where 
excision is not undertaken, extension of the disease to the 
optic nerve and so to the brain is exceedingly rare. 

For Rheumatic Iritis the general treatment is the same — 
salicylate of soda, aspirin, etc. — which is found useful for 
rheumatic symptoms in other parts of the body. In 
Gonorrheal Iritis, too, treatment with salicylate of soda is 
the most successful. 

The treatment of Chronic Iritis, in so far as the general 
system is concerned, must consist in correcting any derange- 
ment of the health which may be present, and particular 
attention should be given to the functions of the gastro- 
intestinal tract. Locally sub-conjunctival saline injections 
(see chap, xv.) frequently render valuable assistance. 

Inflammation of the Ciliary Body : Cyclitis.— Cyclitis, 

as has been stated, attends all cases of severe acute primary 
iritis, and often many of the slighter cases, whatever be 
their etiology, as has been demonstrated by pathological ex- 
amination. Yet very frequently there are no clinical signs 
of its presence, or they are masked by those of the iritis. 
The most common clinical sign of cyclitis in these cases is 
fine punctate deposits — often so fine as to be discernible 
only with the combined focal method, or with the corneal 



361 



DISEASES OF TIIE EYE. 



[chap. XI. 



microscope— on the back of the cornea, with, it may he, 
slight turbidity of the aqueous humour, and occasionally 
the formation of a small pseudo-hypopion. The ciliary 
processes it is which secrete the aqueous humour ; and, when 
they are inflamed, the inflammatory products are liable 
to pass from them, and to appear in the above forms in the 
anterior chamber. 

Owing to gravitation, the lower quadrant of the cornea 
is the part on which the punctate deposits are usually 
precipitated. The part of the cornea which is thus affected 
is often of a triangular shape, the base of the triangle cor- 
responding with the lower margin of the cornea, the apex 
being directed towards the centre of the cornea, with the 
finer dots near the apex. The triangular shape results 
from the motions of the eyeball. In many cases, however, 
nearly the whole cornea is more or less affected. 

In cases where the punctate corneal deposits continue 
for a length of time — in consequence of the resulting de- 
generation of the endothelium on the posterior corneal 
surface — permanent secondary changes in the true cornea 
take place, and a consequent triangular opacity at the 
lower part of the cornea will ever afterwards indicate the 
nature of the process which has gone before. 

Opacities in the vitreous humour — which is also nourished 
by the ciliary processes — especially in its -anterior part, 
are another frequent result and sign of cyclitis. 

But cyclitis is sometimes seen without iritis. Its signs, 
in a severe acute case, in addition to those above mentioned, 
are : — Masked circumcorneal injection, pain on pressure 
of the ciliary region, deep anterior chamber owing to hyper- 
secretion of the aqueous humour, and (edema of the upper 
lid. The danger of increase of the intra-ocular tension is 
great, owing to the tendency to blocking of the angle of I lie 
anterior chamber with inflammatory exudation. In some 
cases the inflammatory products are thrown out abundantly 



CHAP. XI.] 



THE WEAL TRACT. 



3G5 



behind the iris in the posterior chamber, causing a total 
posterior synechia (see p. 350) with the result that the 
posterior chamber becomes completely obliterated ; and, con- 
sequently, the anterior chamber, especially at its periphery, 
is made excessively deep, and the pupil dilated. In these 
cases the intraocular tension is usually reduced. Severe 
eases of cyclitis, or of irido-cyclitis, when they continue long, 
very often become complicated with cataract, owing to 
derangement of the nutrition of the lens. In consequence 
of shrinking of the vitreous humour, detachment of the 
retina is another frequent complication of these cases. 
Finally, shrinking of the globe (phthisis bulbi) is in many 
instances the ultimate result. 

In chronic cyclitis, the circumcorneal injection is slight. 
The anterior chamber is often at first deeper than normal, 
owing to hypersecretion of aqueous humour from the ciliary 
body ; there are punctate opacities on the posterior surface 
of the cornea ; and the anterior part of the vitreous humour 
is filled with fine dust-like opacities. Iritis may come 
on (chronic irido-cyclitis), and glaucomatous increase of 
tension owing to blocking of angle of the anterior chamber. 
Unless increase of tension give rise to it, pain is not often 
present. 

.Syphilitic Cyclitis. — Unless when associated with syphi- 
litic iritis, syphilitic cyclitis cannot be recognised as 
such. 

*>Syphilitic Gumma of the Ciliary Body. — This is rare, 
and belongs to the tertiary stage of syphilis, although it is 
sometimes seen much earlier. It is always preceded by 
acute irido-cyclitis of the usual plastic type. It appears 
at first as a small circumscribed nodule with smooth round 
surface slightly raised over the surface of the sclerotic in 
the ciliary region. It increases in size sometimes very 
rapidly — and is then attended by violent iritis and much 
pain — and again but slowly. It may attain the size of a 



36G DISEASES OF THE EYE. [chap. xi. 



pea or even of an almond, and may extend some way 
around the cornea, presenting a reddish, yellowish, or bluish 
colour. After a time, in the less severe cases, the gumma 
becomes smaller and disappears, leaving a dark cicatrix in 
the sclerotic. But in other cases it breaks through the 
sclerotic, although very rarely through the conjunctiva, 
by destruction of tissue, and when this has taken place the 
tumour grows smaller and undergoes absorption, and the 
eye becomes phthisical. The interval between the appearance 
of the gumma and completion of the process is from a few 
days in the very acute cases, to several weeks in the more 
chronic cases. The gumma may also grow into the anterior 
chamber, and but rarely into the vitreous humour. The 
bulbar conjunctiva is hypera3mic and often chemotic. In 
the cornea there is generally a slight diffuse opacity with 
stippling of the epithelium, and there may be posterior 
punctate deposits. The severe acute cases are accompanied 
by intense interstitial keratitis, oedema of the upper lid, 
and violent pain. The mildest cases may end with retention 
of fair vision, but in most instances serious damage to 
sight results, while in very many vision is totally lost, 
and the eye becomes phthisical. In many of the recorded 
cases the eye was excised in the -acute inflammatory stage 
on account of agonising pain. 

*Tubercular Cyclitis. — This is frequently associated with 
tubercular iritis, although its presence cannot be clinically 
detected. Yet in some cases the disease in the ciliary body 
assumes the form of a large nodule, or even a tumour of 
considerable size — or there may be more than one of these 
— and causes staphylomatous bulging at the corneo-scleral 
margin, which may go on to rupture externally. 

Treatment of Cyclitis. — This follows very much the lines 
of the treatment of iritis. Atropin, by paralysing the 
ciliary muscle, acts favourably on the disease. Yet, if 
the pupil be dilatable, atropine causes engorgement of the 



CHAP. XI.] 



THE UVEAL TRACT. 



3G7 



ciliary body by the blood driven out of the iris. Con- 
sequently, its effect on the symptoms must be watched, and 
it may become necessary to dispense with its use, and even 
for a time to substitute a myotic. Hot fomentations to 
the eye, and a warm bandage, and, in acute cases, leeching 
at the external canthus are serviceable. In chronic cyclitis 
subconjunctival injections of solution of salt are indicated ; 
and, if the intraocular tension become high, paracentesis 
of the anterior chamber should be performed. In syphilitic 
gumma of the ciliary body an active mercurial treatment, 
and in tubercular disease treatment with tuberculin, afford 
the best prospects of cure. 

inflammations of the Chorioid. — There are two chief 

forms of inflammation of the chorioid {^opuov, the chorion ; 
hence chorioid, like the chorion), the exudative and the 
purulent. Of the exudative form, again, there are several 
kinds, namely, disseminated chorioiditis, central senile gut- 
tate chorioiditis, central chorioiditis, and syphilitic chorio- 
retinitis. 

Disseminated Chorioiditis. — The usual Ophthalmoscopic 
Appearances of this disease consist either in round white 
spots of different sizes with irregular black margins, or in 
small spots of pigment, these changes being surrounded by 
healthy chorioidal tissue ; or, there may be few or no white 
patches, but rather spots of pigment surrounded by a pale 
margin. The retinal vessels pass over, not under, the 
patches. The number of these patches or spots varies 
according to the intensity of the disease. Their position is 
at first at the periphery of the fundus only, but later on 
they appear also about the posterior pole of the eye. 

These appearances, however, represent a rather late stage 
of the disease, the early stage not usually coming under ob- 
servation. It consists in small circumscribed plastic exuda- 
tions into the tissue of the chorioid, which, if seen with the 
ophthalmoscope, give the appearance of pale pinkish-yellow 



3G8 



[chap. XI. 



or greyish spots behind the retinal vessels. The exudations 
may undergo absorption, leaving the chorioid in a fairly 
healthy state ; but, more usually, they give rise to atrophic 
cicatrices, in which the retina becomes adherent, with pro- 
liferation of the pigment-epithelium layer in their neigh- 
bourhood, and hence the white patches with black margins 
above described. This is the form of chorioiditis which is 
often associated with inflammatory processes in the iris or 
ciliaiy body, either as a primary or secondary affection. 
But, again, in many instances the disease does not extend 
beyond the chorioid. 

Sometimes, in addition to the above changes, the pigment- 
epithelium layer all over the fundus becomes atrophied, 
exposing to view the vascular network of the chorioid, while 
here and there small islands of pigment are present. 

Opacities in the vitreous humour are sometimes found. 

Symptoms. — Diminution in the visual acuity, especially 
if the macula be involved ; there may also be subjective 
sensations of light or colours, positive scotomata (dark areas 
visible to the patient), and distortion of objects (metamor- 
phopsia), or alteration in their size (megalopsia and micropsia). 
Night-blindness is not uncommon. 

Causes. — Disseminated chorioiditis is due to acquired 
syphilis in a considerable number of the cases. And 
possibly in some it may be tubercular. But in a very 
large proportion of cases no ascertainable cause exists ; 
and these cases, there is reason to suspect, are congenital, and 
probably many of them are dependent on an inherited 
syphilitic taint. In eyes with congenital cataract, patches 
of chorioiditis are often found. 

Prognosis. — Disseminated chorioiditis is always a serious 
and very chronic disease, fresh spots of exudation making 
their appearance from time to time, and complete recovery 
cannot be looked for. The degree of defect of sight it may 
cause in the early stages depends much on the extent to 



CIIAP. XI.] 



TEE UVEAL TRACT. 



369 



which the region of the macula lutea has become involved. 
In advanced cases the optic nerve and retina become 
atrophied, and still later the lens becomes cataractous. 

Treatment. — In fresh cases due to acquired syphilis, a 
prolonged but mild course of mercurial inunctions is the 
most suitable measure, to be followed by a lengthened course 
of treatment with iodide of potassium. Where an inherited 
syphilitic taint is suspected, iodide of iron or iodide of potas- 
sium internally may be of use ; while, in the cases due to 
other causes, small closes of perchloride of mercury may be 
given ; and in all cases, from whatever cause, subconjunctival 
injections of 4 per cent, solution of common salt are indicated. 
Dark protection spectacles should be worn, and absolute rest 
of the eyes from all near work insisted upon, so long as 
the disease is active. 

*Central Senile Guttate Chorioiditis. — Under this name 
an appearance has been described by Mr. Waren Tay and 
others, which consists of fine white, pale yellow, or glistening 
dots, best seen in the upright image, and situated chiefly 
about the macular region, or between this and the optic 
papilla. These dots are due to colloid degeneration with 
chalky formations in the vitreous layer of the chorioid, 
which give rise to secondary retinal changes. The appear- 
ances must not be confounded, as they sometimes have 
been, with those of retinitis punctata albescens (chap, xvi.), 
which is an entirely different disease. The functions of 
the retina usually suffer in a marked manner, so that a 
partial central scotoma may be produced ; but some cases 
have been observed, in which vision was but little, or not 
at all, affected. 

This disease attacks both eyes,- either simultaneously or 
with an interval, and is most often seen in persons of ad- 
vanced life, although it is also found in middle age, and even 
in youth. It should always be looked for in cases of incipient 
cataract ; for when the lental opacity is more advanced it 

24 



370 



DISEASES OF THE EYE. 



[CHAP. XI. 



cannot be seen, while functional examination docs not then 
reveal it. 

Treatment is of no avail. 

"Central Chorioiditis. — Tbis is an exudation at the macula 
lutea, without any similar disease elsewhere in the fundus. 
Absolute central scotoma is its prominent symptom, and 
syphilis its usual cause. 

Treatment. — Active mercurialisation ; and, where this can 
be adopted early, the prognosis for recovery of sight is fairly 
good. Subconjunctival salt injections aid the cure. 

Syphilitic Chorioido-Retinitis. — See Syphilitic Retinitis, 
chap. xvi. 

Tubercle of the Chorioid. — See p. 405. 

Purulent Chorioiditis. — This consists at first in a purulent 
extravasation between the chorioid and retina, and into the 
vitreous humour, recognisable by the yellowish reflection 
obtained from the interior of the eye on illuminating it. 
The eyeball may become hard, the pupil dilated, and the 
anterior chamber shallow. Purulent iritis with hypopyon 
soon comes on, and the cornea may also become infiltrated 
and slough away. There is usually considerable chemosis. 
The eyeball is pushed forwards by inflammatory oedema 
of the orbital connective tissue. The eyelids are swollen 
and congested. There is intense pulsating pain in the eye, 
and radiating pains through the head; and in this stage 
all the tissues of the eyeball are engaged in the purulent 
inflammation, and the condition is termed Panophthalmitis. 

Purulent chorioiditis does not reach this latter stage in 
every case, but may remain confined chiefly to the chorioid, 
vitreous humour, and iris. The pain in these cases is not 
severe ; and when the affection occurs in children it may be 
mistaken for glioma of the retina (chap, xvi.) ; indeed, the 
name pseudo-glioma has, unfortunately, been given to it. 
It is distinguished from glioma by the muddy vitreous 
usually present with it, by the posterior synechia, and by 



CHAP. XI.] 



THE UVEAL TRACT. 



371 



the retraction of the periphery of the iris, with bulging 
forwards of its pupillary part. 

Prognosis. — The ultimate result in the vast majority 
of cases is loss of sight, with phthisis bulhi. The severe 
cases go on to rupture of the eyeball through the cornea or 
sclerotic, after which the pain subsides. It would seem from 
the description of authors who have seen much of epidemic 
cerebro-spinal meningitis, that a certain number of cases of 
irido-chorioiditis occurring in the course of that disease do 
recover with retention of good sight. 

The shrunken eyeballs produced by panophthalmitis are 
not generally painful on pressure. They are not very liable 
to give rise to sympathetic ophthalmitis, and the latter 
statement is also true of the acute purulent process itself. 
It is cases of traumatic plastic irido-chorioiditis which 
produce sympathetic ophthalmitis. 

Causes. — The most common causes of purulent chorioiditis 
are perforating wounds of the eyeball, whether accidental or 
operative ; foreign bodies piercing and lodging in the eyeball ; 
and purulent keratitis. It may also come on suddenly in 
eyes which are the subjects of incarceration of the iris in a 
corneal cicatrix, through infection of the incarcerated iris. 

Again, it is seen as embolic or metastatic chorioiditis, in 
connection both with epidemic and sporadic cerebro-spinal 
meningitis (chap, xx.) ; in some cases of metria, similarly 
as purulent retinitis (chap, xvi.) ; in pyseinia of the ordinary 
type ; and in endocarditis. 

In infancy and childhood, besides its occurrence with 
cerebro-spinal meningitis, it has been known to be caused 
by, or associated with, inherited syphilis, measles, bronchitis, 
diarrhoea, hooping-cough, and omphalophlebitis; and it is more 
than probable that, in every idiopathic case, some infective 
Mood disease is the fundamental cause of the process, although 
it may not always be possible to determine its existence. 

Tr'-<iiin<id may \><i said to be powerless in this disease. 



372 



DISEASES OF THE FY A. 



[chap. XI. 



The utmost one can do is to endeavour to diminish the pain 
in the very severe cases by warm fomentations, poultices 
containing conium, hypodermic injections of morphia, or, 
finally, by giving exit to the pus by a free incision in 
the eyeball, followed by a copious irrigation with weak 
sublimate lotion, so as to wash out the whole contents 
of the scleral cavity. Quinine and chlorate of potash are 
suitable internal remedies. 

Enucleation of the eyeball should not be undertaken 
during purulent chorioiditis in the acute stage, as it is liable 
to lead to purulent meningitis and death. 



Sympathetic Ophthalmitis, and Sympathetic 
Irritation. 

Introductory. — By the term Sympathetic Ophthalmitis we 
understand a general plastic uveitis (plastic inflammation of 
iris, ciliary body, and chorioid) of one eye, which has been 
caused by a plastic uveitis of the other eye, the latter 
condition being most commonly due to a perforating trauma, 
or other perforation of the eyeball. Or, the sympathetic 
ophthalmitis occasionally consists in an optic neuritis or 
chorioiditis. 

There are no such diseases as sympathetic cataract, con- 
junctivitis, detachment of the retina, keratitis, scleritis, etc. 

The term 1 sympathetic ' in this connection is an old one, 
and probably would not be employed had the disease to 
be named at the present time. 

Sympathetic ophthalmitis is not a fifth-nerve reflex 
phenomenon. It is, as stated, a uveitis, and often also an 
optic neuritis, which has arisen by transmission of certain 
undetermined micro-organisms, from the injured eye, in 
which uveitis has been set up, to the sympathising eye. No 
sympathetic uveitis can be developed in the second eye, until 
after uveitis in the lirst eye has commenced. A perforating 



CHAP. XI.] 



THE UVEAL TRACT. 



373 



injury of the eyeball, or other perforation, which does not 
produce uveitis in that eye, does not give rise to sym- 
pathetic ophthalmitis in the fellow eye. Yet, traumatic 
uveitis in the injured eye does not cause sympathetic 
ophthalmitis in every case. 

The eye which has received the perforating injury is 
spoken of as the exciting eye, and its fellow, which becomes 
the subject of sympathetic ophthalmitis, as the sympathising 
eye. The eyes are also spoken of as the injured eye, and the 
sympathising eye ; also as the first eye, and the second eye. 1 

While sympathetic ophthalmitis is not a reflex condi- 
tion, there is an affection known as sympathetic irritation, 
which is a true fifth-nerve reflex neurosis. These affections, 
although sometimes closely associated clinically, are quite 
distinct from each other. 

Before treating of sympathetic ophthalmitis, it will be 
convenient to state what is necessary concerning sympathetic 
irritation. 

Sympathetic Irritation. — This may be caused by almost 
anything which produces irritability of the ciliary nerves in 
the first eye — e.g., foreign bodies on the cornea or under the 
upper lid, losses of substance of the corneal epithelium, 
anterior staphyloma, acute glaucoma, iritis, dislocation of 
the crystalline lens, etc., etc. 

Amongst the many causes of sympathetic irritation is an 
irritable shrunken globe, whether the latter condition be the 
result of a uveitis from a perforating injury, or of an 
idiopathic uveitis ; and an irritable shrunken globe may give 
rise to sympathetic irritation in the fellow eye at any time, 
even after many years. Having remained quiet for so 
long, the shrunken eye begins to lacrimate, and becomes 
painful find injected. A fresh injury to the stump may be 
the cause of this, or it may be ossification of its chorioid, 

1 German authors term the injured eye the sympathising eye, and 
the second eye the sympathised eye. 



374 



DISEASES OF THE EYE. 



[chap. XI. 



and the irritation, whatever its cause, may be transmitted 
to the sound eye. 

The most common symptoms of sympathetic irritation of 
the second eye are : photophobia, lacrimation, vascular in- 
jection of the front of the eyeball, and accommodative 
asthenopia, and, in a well-marked case, these symptoms 
become intensely distressing to the patient. Neuralgia in 
the orbit and brow, and retinal asthenopia sometimes occur. 

Sympathetic ophthalmitis is also often caused by a 
shrunken fellow eyeball, in which uveitis, indicated by the 
presence of irritability, is present {vide infra) ; and of great 
importance is the question : What relation, if any, has sym- 
pathetic irritation to sympathetic ophthalmitis in such cases 1 
Is sympathetic irritation to be regarded as a reliable and 
essential premonitory symptom of sympathetic ophthalmitis 1 
The answer is in tho negative. Sympathetic irritation may 
last an indefinitely long time, without being followed by 
sympathetic ophthalmitis. Further, although some sign or 
signs of sympathetic irritation often do precede the onset 
of sympathetic ophthalmitis, yet in many cases every such 
sign is wanting. It is, therefore, in view of the latter fact, 
wrong to postpone a prophylactic enucleation, until sym- 
pathetic irritation shows itself. 

Treatment. — When sympathetic irritation is caused by 
an irritable shrunken globe on the opposite side, it can 
be immediately relieved by removal of the stump. Rest 
in a dark room and sedative measures, while they may 
seem to cure, merely lead to disappointment, owing to the 
almost certain return of the symptoms, when the eye is 
brought into use again. Moreover, as sympathetic irritation 
does often precede sympathetic .inflammation, it is wise to 
enucleate the exciting stump in order to assure the safety of 
the second eye. 



Sympathetic Ophthalmitis. Diagnosis. — The inflamma- 



CHAP. XI.] 



THE UVEAL TRACT. 



375 



tion of the uveal tract in the sympathising eye has no 
characteristics which enable us to make the diagnosis 
' Sympathetic Ophthalmitis,' for precisely the same plastic or 
sero-plastic uveitis, as the case may he, is seen under other 
conditions ; nor is the state of the first eye, taken alone, a 
certain guide. To arrive at a diagnosis, it is necessary to 
weigh the following data, and to take them collectively into 
consideration : — 

1. The condition of the exciting eye, and the nature of the 
injury to, or disease of, that eye. 

2. The condition of the sympathising eye. 

3. The interval that has elapsed between the injury to 
the exciting eye, and the onset of the uveitis in the 
sympathising eye. 

4. The state of the general system. 

1. The Condition of the Exciting Eye. — As already stated, 
perforating injuries, or perforating corneal ulcers, of the first 
or exciting eye, which are followed by plastic uveitis, are by 
far the most common causes of sympathetic ophthalmitis. 
The position of the wound in the eye has no influence in 
the production of sympathetic ophthalmitis. Uveitis in the 
injured eye is due to infection of the wound by micro- 
organisms derived from the foreign body, or instrument, 
which has caused the wound, but sometimes perhaps from 
the surface of the eye, or from the atmosphere. 

Either a purulent uveitis, or a plastic uveitis, may result 
from the injury. 

Purulent uveitis of a not very pronounced type (purulent 
infiltration of the vitreous humour, iritis, hypopyon) is very 
occasionally followed by sympathetic ophthalmitis, but, and 
it is a remarkable clinical fact, the marked purulent uveitis, 
which is called panophthalmitis (p. 370), may be said never to 
give rise to it. It is obviously not a pyogenic micro-organism 
which causes sympathetic ophthalmitis, for, if it were, the 
latter would be a purulent process; but it is some specific 



37G 



DISEASES OF THE EYE. 



[chap. XI. 



micro-organism ; and it can hardly be doubted that in those 
rare instances in which sympathetic ophthalmitis has followed 
on slight purulent uveitis, this specific organism has been 
present in the injured eye along with the staphylococcus. 

If the infection of the injured eye be purulent, the in- 
flammatory reaction in it comes on within the first thirty-six 
hours after the injury ; while the fibrinous or plastic inflam- 
matory reaction, caused by the specific organism, which is 
so dangerous in relation to sympathetic ophthalmitis, declares 
itself in the injured eye less quickly and more insidiously. 

In the case of the latter infection, the injection and 
irritation, the immediate results of the injury, disappear 
in a few days, only soon to return. The pupil then begins 
to dilate less well to atropine, the tissue of the iris 
becomes less distinctly seen, some posterior synechia? 
form, and some opacities appear in the vitreous humour. 
At first there is little or no pain spontaneously or on 
pressure. Then more synechia? form, the iris stroma 
becomes more indistinct and discoloured, often of a dull 
greenish or yellowish grey, and the pupil becomes occluded. 
The anterior chamber becomes shallower than normal, and 
the intraocular pressure is diminished. Sight is much 
impeded by exudation in the pupil and by opacities 'in 
the vitreous, and, in case of detachment of the retina from 
shrinking of the inflammatory products in the vitreous 
humour, it may be reduced in a marked degree. There is 
often pain on pressure of the eyeball, and the latter soon 
begins to be diminished in size and becomes soft to the 
touch, while the pressure of the tendons of the orbital 
muscles on this soft eyeball gives rise to deep furrows on 
its surface. In short, the injured eye has now become 
phthisical, and sight is quite lost. This entire process may 
be completed in three or four weeks, or it may occupy a 
considerably longer time. 

The danger of sympathetic ophthalmitis supervening on 



THE UVEAL TRACT. 



377 



a perforating injury of the first eye commences with the 
onset of plastic uveitis in the injured eye — although the 
inflammatory process in the second eye does not develop 
until after a certain interval {vide infra) — and this danger 
is present, not only all through the acute process in the 
injured eye, but also after this has subsided, and when 
the eye has become shrunken, and even for many years more. 

Shrunken eyeballs, as just stated, are liable to cause 
sympathetic ophthalmitis. Pain on pressure of the ciliary 
region in them, showing, as it does, the presence of inflam- 
mation of the ciliary body, is an important danger-signal ; 
but the absence of pain on pressure is not conclusive of the 
absence of cyclitis, for the latter may exist to only a slight 
and yet dangerous degree, or the ciliary body may be 
detached and out of reach of pressure. 

The presence of a foreign body in the interior of the 
injured eye does not necessarily lead to sympathetic ophthal- 
mitis by the inflammatory reaction which it may cause ; for 
an aseptic foreign body in the eye will cause an active 
inflammatory reaction ; yet this latter, not being of bacterial 
origin, will not in its turn give rise to sympathetic 
ophthalmitis. There are, however, few foreign bodies, 
except atoms of hot metal, which can be guaranteed as 
free from infective material ; hence, as a rule, the presence 
of a foreign body within the eye augments the danger of a 
perforating injury. 

As in accidental perforating injuries, so also the wounds 
made in the sclerotic or cornea in surgical operations; 
especially in cataract extractions, may be followed by plastic 
uveitis, which will produce sympathetic ophthalmitis. In 
consequence of the thorough antiseptic measures now in 
use, inflammatory processes after cataract extractions are 
very much less common than they used to be. 

Perforations caused by ulcers of the cornea sometimes 
give rise to uveitis, which may be followed by sympathetic 



378 



DISEASES OF THE EYE. 



[chap. XI. 



ophthalmitis ; hut this is a rare event, although some iritis 
is present with almost every severe corneal ulcer, and 
especially with those which tend to perforate. It is not 
easy to assign a reason for the rare occurrence of sym- 
pathetic ophthalmitis in these cases. 

In how far plastic uveitis of the first eye, which is not 
due to perforating injuries or ulcers, is capable of being the 
cause of sympathetic ophthalmitis is an important question. 
Intraocular tumours, which have not yet perforated the 
sclerotic, especially sarcoma of the chorioid, very occasion- 
ally set up a uveitis, which leads to sympathetic ophthalmitis. 
In these cases necrosis of the tumour has generally set in. 
Again, ruptures of the eyeball from blows, which usually 
occur in the ciliary region, without rupture of the con- 
junctiva — subconjunctival ruptures of the sclerotic — some- 
times come under our notice (p. 344). They almost invariably 
run a course free from inflammation, or even irritation of 
the injured eye, owing to the unbroken conjunctiva, which 
covers the rupture, and prevents the access of infecting 
bacteria ; and, consequently, they may be said not to cause 
sympathetic ophthalmitis. It is probable that in the few 
cases of this injury in which uveitis in the injured eye 
and sympathetic ophthalmitis in the second eye appeared, 
there existed some small opening in the apparently sound 
conjunctiva. 

Cases of gonorrheal ophthalmia have been published in 
which sympathetic ophthalmitis came on. But these were 
all cases in which ulceration, followed by perforation of 
the cornea, took place; and, hence, in which infection by 
bacteria other than the gonococcus was quite possible. 

2. The Condition of the Sympathising Eye. — The diseased 
process in the second or sympathising eye, as has already 
been stated, is, with certain rare exceptions, an inllammation 
of the uvea, of a plastic or fibrinous type, but never puru- 
lent, and almost always begins in the uvea, or, at any rate, 



CHAP. XI.] 



THE UVEAL TRACT. 



379 



is commonly first discovered there as iritis. In the rare 
exceptions referred to, optic neuritis is the first sign of 
sympathetic ophthalmitis, uveitis coming on subsequently ; 
and, yet more rarely, optic neuritis has been seen as the 
one and only sympathetic inflammation, the uvea remaining 
unaffected. It is, however, held by some, that optic neuritis 
is the first sign in the sympathising eye in nearly all 
eases, if only they could be examined before opacities in 
the vitreous humour, aud exudation in the pupil, interfere 
with an ophthalmoscopic diagnosis. 

The appearance of the optic neuritis, or papillitis, as seen 
in these cases, consists in hyperemia of the disc, without 
much swelling of it, but with slight woolliness of its margin, 
the opacity spreading a short distance into the surrounding 
retina. The veins are distended, and the arteries are normal. 
The sight is considerably affected, and there is often rather 
severe headache. The remedy for sympathetic papillitis, 
occurring alone, is removal of the exciting eye, and a few 
days after the operation the beneficial effect on the optic 
nerve inflammation begins to show itself. 

There are no reliable premonitory symptoms of the attack 
of uveitis in the sympathising eye. As already stated, in 
many cases sympathetic irritation does precede the first 
signs of sympathetic uveitis, but it does not always do 
so ; and when sympathetic irritation does appear, it need 
not always indicate the approach of sympathetic uveitis. 

The early signs of the actual presence of uveitis in the 
sympathising eye are : — some fine punctate deposits on 
the posterior surface of the cornea, and these are often the 
first symptom ; slight peri-corneal injection ; slight opacity 
of the aqueous humour ; some discoloration and indistinct- 
ness of the iris; contraction of the pupil, but as yet no 
synechias; some fine opacities in the vitreous humour; and 
slight loss of sight owing to these changes. 

Posterior synechia' soon begin to form, and the adhesions 



380 



DISEASES OF THE EYE. 



[chap. XI. 



occur in the most serious cases, not merely between the 
margin of the pupil and the anterior capsule of the lens, 
but, after a little while, between the whole of the posterior 
surface of the iris and the capsule — total posterior synechia. 
The exudation which causes this extensive adhesion soon 
pushes the iris forward — iris bombe— and renders the 
anterior chamber shallow; but after a time, when the 
fibrinous exudation begins to shrink, the anterior chamber 
becomes deep at its periphery, owing to retraction of the 
iris. The iris gradually becomes more altered, its tissue 
more dull, discoloured, and indistinct, while large vessels 
form in it. Occasionally, in the anterior chamber a small 
pseudo-hypopyon is seen, formed by the fibrin which floats in 
the aqueous humour, some of which has gravitated. 

The intraocular tension may become high, often very high, 
owing to blocking of the angle of the anterior chamber with 
inflammatory products, and this glaucomatous tension is 
apt to be attended by great pain. In consequence of the 
presence of such extensive adhesions, eserine and pilocarpine 
have no influence on this high tension, and the temptation 
to perform an iridectomy very great. Yet, it may be 
stated at once, there is no more disastrous, mistake in 
ophthalmic practice than any operative interference at 
this period. Far from doing good, an iridectomy is almost 
certain to do harm. It is impossible, owing to the dis- 
organised state of the iris and its close adherence to the 
anterior capsule, to obtain anything like a satisfactory 
coloboma ; and even if the tension be reduced for a day 
or two after the operation, it soon becomes as high as before, 
in consequence of the rapid filling up of the coloboma by 
proliferation of the inflammatory products, while the trau- 
matism of the operation only seems to lend additional violence 
to the inflammation. 

In the further progress of the disease, the cornea gradually 
becomes more or less opaque, from derangement of its 



CHAP. XI.] 



■J III-: UVEAL TRACT. 



381 



posterior epithelium by the punctate deposits of fibrin upon 
it, and the crystalline lens becomes cataractous. After a 
time the high tension disappears, and gradually, owing to 
shrinking of the vitreous humour, low tension comes on. 
Vision, already very bad, sinks further. The eyeball be- 
comes less in size and very soft to the touch, and phthisis 
bulbi, with complete blindness, is presented. This entire 
process may occupy many months, and is often interrupted 
by short periods of slight improvement in the symptoms, 
which raise the hope of the patient and of the surgeon. 
Even when phthisis bulbi and complete blindness have 
come on, danger to the second eye is not at an end, for 
in these shrunken eyeballs active infective uveitis continues 
for lengthened periods, or is liable to light up now and 
then, and to bring on sympathetic mischief. 

In rare cases, the sympathetic uveitis comes on with 
violent pain, chemosis, and swelling of the eyelids, and 
ends rapidly in phthisis bulbi. 

On the other hand, there is a less severe class of cases, 
in which total posterior synechia does not form, the 
pupillary margin alone becoming adherent, and these cases 
may run a ^comparatively favourable course. 

A yet milder, and not uncommon, form of sympathetic 
uveitis is that in which the only signs are : — punctate deposits 
on the posterior surface of the cornea, and increased depth 
of the anterior chamber, without any iritis. The punctate 
deposits are at first often so fine as to be undiscoverable, 
unless by aid of a high convex lens behind the sight-hole 
of the ophthalmoscope, or with a corneal microscope. This 
form of sympathetic ophthalmitis is termed serous sympa- 
thetic uveitis, and its prognosis is favourable. Its one 
danger consists in the increased intraocular tension which 
is liable to come on, but which should not tempt the 
surgeon to employ an iridectomy, whereby a mild process 
may be converted into a severe one. 



382 



DISEASES OF THE EVK 



[CHAP. XI. 



More common than this typical serous uveitis are cases 
in which some fibrin is thrown out, with resulting posterior 
synechia at the pupillary margin, and where small round 
yellowish-white deposits may be found with the ophthal- 
moscope in the chorioid — called sympathetic disseminated 
chorioiditis — especially towards the periphery of the fundus. 
In some cases the iris is free from inflammation, the chorioid 
alone being affected in the manner mentioned. This form of 
sympathetic ophthalmitis is not attended by much irritation 
of the eye, nor need vision be much affected. The corneal 
deposits very gradually increase in number, and consequently, 
vision becomes affected to some extent, and then, if the 
tension do not increase, the signs and symptoms after a 
time very slowly abate, and a normal state is re-established. 
But relapses are liable to occur even after some months, 
and they may assume the very dangerous fibrinous type. 
So that, even in these mildest cases, the utmost care in 
treatment and prognosis is needed. 

Removal of the exciting eye does not cure the uveitis in 
the sympathising eye [vide infra?). 

3. The Interval that has elapsed between the Injury to the 
Exciting Eye, and the Onset of Uveitis in the Sympathising Eye. 
— So far as our present knowledge based on reliable cases 
enables an opinion to be formed, the shortest interval which 
occurs between the injury to the first eye, and the onset of 
uveitis in the second eye, is fourteen clays, and very few 
cases with this shortest interval have been reported. The 
period between the sixth and twelfth week after the injury 
seems to be the most dangerous. In 170 of the 200 cases 
collected by the Committee on Sympathetic Ophthalmitis of 
the Ophthalmological Society the second eye was attacked 
within the first year after the injury to the exciting eye. 
In only 12 of the 200 cases was the interval more than one 
year, and the longest interval was twenty years. 

4. The State of the General System.— As the subjects of 



CHAP. XI.] 



THE UVEAL TRACT. 



383 



traumatic plastic uveitis in one eye are not immune n gainst 
plastic uveitis in the other eye due to syphilis, rheumatism, 
tubercle, diabetes, etc., it is necessary in each case to con- 
sider, whether the attack in the second eye may not be 
a symptom of some systemic condition, rather than a 
sympathetic uveitis. 

From the above it appears, then, that the diagnosis of 
sympathetic ophthalmitis depends on the following evidence: 
— (1) As regards the exciting eye : an ectogenic infection ; 
unless in those rare cases where a chorioidal sarcoma produces 
the infective substance. (2) As regards the sympathising 
eye : an inflammatory process of a plastic type, which attacks 
all three portions of the uveal tract, is very chronic in 
its course, often improves for a while, but relapses again. 

(3) As regards the interval between the perforating injury 
in the first eye, and the appearance of sympathetic ophthal- 
mitis : an interval of at least fourteen days is required. 
The period between the sixth and twelfth week is the most 
dangerous, and very few cases occur after the first year. 

(4) As regards the general system : when careful examin- 
ation of it does not reveal any condition, which might be 
the cause of uveitis in the second eye, the probability of this 
uveitis being sympathetic is increased. 

Prognosis. — The prognosis of sympathetic uveitis is, in 
general, serious ; yet it need not be quite hopeless, for even in 
severe cases very occasionally, and of course more frequently 
in the less severe cases, the sympathising eye does recover 
after prolonged treatment, with a useful amount of vision. 
But in these rare cases which undergo cure, the eyes are 
liable to occasional recurrences of the uveitis, and at least a 
year should elapse since the last recurrence, before a definite 
end to the diseased process can be said to have been reached. 

The prognosis of sympathetic papillitis is quite favourable, 
when once, the exciting eye has been removed. 

Treatment. — Measures calculated to prevent the onset 



384 



DISEASES OF THE EYE. 



[chap. XI. 



of sympathetic ophthalmitis are of the first importance. 
Where the injury is so extensive as to make all prospect 
of saving sight id the first eye hopeless, immediate excision 
of that gloh e is ohviously indicated. Where some pros- 
pect of saving sight in the injured eye exists, attention is 
claimed in the first instance by the wound, which, in those 
cases that come for surgical aid sufficiently early, is to be 
protected from secondary infection by careful antiseptic 
cleansing, abscission of any prolapsed portions of the uvea, 
suturing of the wound in suitable cases, and dressing and 
bandage. 

Should the wound be already infected, excision of the 
injured eyeball is called for. No temporising is admissible 
— even some useful vision being, for the time, retained by 
the injured eye is not a contra-indication to the operation. 

Where sight in the injured eye is lost, it will not be 
difficult for the surgeon to recommend excision of the eyeball, 
and even to urge it on the patient ; but when some useful 
sight is still retained, it is not so easy to press this advice, 
although that should be done. We know, indeed, that in 
some cases of traumatic uveitis sympathetic uveitis does 
not supervene ; and, provided the first eye be not too 
much disorganised by the injury, sight even in it may 
ultimately be obtained. But, unfortunately, we are unable 
to foretell whether any given case will run so favourable 
a course ; and to temporise, in the hope that it will do 
so, involves serious danger to the second eye, and, it may 
be, ultimate loss of all sight in each eye. 

In short, it cannot be doubted that there are cases, 
in which, in the present state of our knowledge, we recom- 
mend removal of the injured eye, and where, had we 
decided to run a fearful risk by allowing it to remain, 
not only would sight have been restored to it, but no sym- 
pathetic ophthalmitis would have come on. 

It must be further stated, that we cannot feel sure, that 



CHAP. XI.] 



385 



ou i* removal of the first eye has averted sympathetic 
ophthalmitis from the second eye, uutil four weeks after the 
operation has elapsed. Nearly every ophthalmic surgeon has 
seen cases in which sympathetic ophthalmitis has appeared 
subsequently to excision of the first eye, and in which, at the 
time of the operation, the second eye was perfectly sound. 
There are well-authenticated cases where sympathetic ophthal- 
mitis appeared as long as four weeks after enucleation of 
the injured eye. The assumption is that, in these cases, 
the infective micro-organisms had already gone on their 
journey to the second eye. These cases are deplorable for 
the patient, and very trying for the surgeon, especially 
if the outbreak of sympathetic ophthalmitis should occur 
very soon after — perhaps the day after — the operation. 
Yet where sympathetic ophthalmitis comes on after excision 
of the first eye, the operation need not be regarded as 
having been quite useless ; for experience shows that the 
attack of uveitis in the second eye is then usually of a com- 
paratively mild type, and fairly amenable to treatment. 

In those cases in which the exciting eye has not yet 
been removed, and in which sympathetic ophthalmitis in 
the second eye has commenced, what are our duties 1 In 
the first instance, and at the earliest possible moment, the 
exciting eye should be removed, always "provided that it be 
quite and hopelessly blind. The immediate result on the 
second eye of removal of the first eye under these condi- 
tions is not marked, for the inflammatory process in the 
former seems to proceed as actively as before. But statistics 
show that more sympathising eyes are saved, or partially 
saved, when the injured eye has been removed soon after 
the outbreak of sympathetic ophthalmitis than when the 
injured eye is removed a considerable time after the out- 
break, or not at all. Presumably when the source of supply 
of the infection is withdrawn, the virulence of the sympathetic 
disease gradually subsides. 

25 



;isg 



DISEASES OF THE EYE. 



[CHAP. XI. 



But no exciting eye, which possesses even a slight degree 
of sight, should be removed when once sympathetic ophthal- 
mitis has appeared. For it may well happen, that the 
sympathising eye becomes entirely lost, while the exciting 
eye ultimately retains some degree of useful sight. Great 
caution is therefore required in deciding whether the ex- 
citing eye is capable of recovering to a certain extent, and 
this frequently is a matter of considerable difficulty. Even 
a partially phthisical eyeball may sometimes ultimately come 
round sufficiently to gain useful vision. Schirmer lays 
down the following rule : — When sympathetic ophthalmitis 
has broken out, the exciting eye should not be removed, 
unless it be absolutely blind ; or unless — if it still possess 
merely perception of light — it has been for several weeks 
very soft, and reduced in size ; or that, by reason of ex- 
tensive corneal opacity, all hope of restoration of form- 
vision must be abandoned. 

If sympathetic ophthalmitis have broken out, either before 
or after removal of the exciting eye, the treatment and care 
of the sympathising eye to promote its recovery must be 
considered. This consists in the use of atropine, warm 
fomentations, and subconjunctival saline injections (chap, xv.), 
which latter are held by some to be very beneficial when 
high tension is present. With these local means is combined 
a general and prolonged course of mercurialisation — mer- 
curial inunctions or calomel internally, or both, care being 
taken to avoid any severe stomatitis. Salicylate of soda 
is now used in large doses (as much as one hundred and 
fifty grains in the day) by some surgeons.. The patient 
is to be confined in one warm, but well-ventilated room, 
which should be kept almost dark. As this treatment must 
often be carried on for many weeks or even months, it is 
trying for the patient; but it is to be remembered that 
the issue at stake is a fateful one. 

No operation on the iris is to be performed as long as there 



CHAP. XI.] 



THE UVEAL TRACT 



387 



is the slightest inflammation, or tendency to inflammation, 
and this rule holds good, even if the tension of the eye become 
glaucomatous. Premature operative interference ou the iris 
has only the effect of lighting up fresh inflammation; and, even 
if the tension be reduced by an iridectomy — which latter, 
owing to the diseased and degenerated state of the iris and 
the inflammatory exudation behind it, cannot be satisfactorily 
carried out — it will soon again become high. In six months 
or a year after every slight sign of inflammation, or 
tendency to inflammation — of which injection of the ciliary 
vessels on insertion of a spring speculum is not a bad 
criterion — -has passed away, and a longer interval can only 
be of advantage, it may be allowable to perform an 
operation with the object of making an artificial pupil, 
always provided that there is good prospect of materially 
improving vision by this means. It must be 'remembered 
that, while every operation has its risks, the risks are un- 
usually great in such disorganised eyes ; and that any loss of 
sight is felt all the more in a case, in which the eye operated 
on is probably the only one possessing even a little vision. 
On the other hand, when success crowns an operation in 
these sad and perplexing cases, the gain is great. 

If it be decided not to remove the exciting eye, after 
sympathetic ophthalmitis has broken out, then the inflamma- 
tory process in it is treated on lines quite similar to those 
above recommended for the sympathising eye, and the 
advice as regards operations is the same. 

Prophylactic Operations used for Sympathetic 

Ophthalmitis, performed on the exciting eye. 

KavAdeatwri (or Excision). — Of prophylactic operations for 
sympathetic ophthalmitis, enucleation of the first eye is 
the only one which is regarded by all ophthalmic surgeons 
as thoroughly reliable, when it is performed in time. 

The speculum having been inserted, an incision is made 
in the conjunctiva all round the cornea, and about G mm. 



388 



DISEASES OF THE EYE. 



[chap. XI. 



removed from the latter. The bulbar conjunctiva is separated 
from the globe freely in all directions with a scissors. With 
a strabismus hook each orbital muscle is caught up, and its 
tendon divided close to the sclerotic. The optic nerve is 
then divided with a strong scissors passed into the orbit, 
either from the median or from the temporal side, as far 
back in the orbit as possible. Finally the edges of the 
conjunctiva are drawn together with a few points of suture. 

Careful aseptic and antiseptic precautions are to be 
employed in connection with enucleation of the globe. Of 
these, next to thorough sterilisation of the instruments, 
irrigation of the cavity of the orbit as soon as the eye- 
ball is removed, with a full stream of sublimate solution, 
1 in 5000, or of sterilised normal salt solution is the most 
important. After the sutures have been applied, the interior 
of the orbit is well covered with xeroform, or other fine 
antiseptic powder, and an aseptic dressing is applied with 
a bandage. The orbit should be similarly dressed every 
twenty-four hours. 

Some cases of meningitis following upon the operation, 
and which have proved fatal, are reported. There can be 
no reasonable doubt but that, in these instances, septic 
matter made its way along the lymphatics of the optic 
nerve to the meninges, and that this septic matter was 
introduced upon the instruments, or escaped, in purulent 
cases, from the interior of the eyeball. Hence the very 
great importance of the careful aseptic precautions above 
indicated. 

An artificial eye (prothesis oculi) can usually be inserted 
after a fortnight, but should not be constantly worn for a 
month at least, as, until that period elapses, it is liable to 
cause irritation and conjunctivitis. 

* Evisceration.— -For mode of performing this operation, 
vide p. 256. Evisceration is not held to be so good a 
safeguard against sympathetic ophthalmitis as excision, 



0 HA P. XI. J 



TUB UVEAL TRACT. 



389 



and is not employed for that purpose, unless where 
it is performed quite soon after the injury, or at any rate 
before uveitis has commenced. The advantage of evisceration 
nver enucleation lies in the better stump provided by it 
for a prothesis, and the consequent better cosmetic effect. 

* Mules Operation. — For the description of this operation 
see p. 257. The objections to and advantages of this operation 
are the same as in evisceration, but it gives a better stump 
than the latter. 

* Adams Frost's Operation (p. 259). — The same remarks 
apply to this method. 

Therapeutic Operations used in Sympathetic Oph- 
thalmitis. — -The field for these operations, if it exist at 
all, is exceedingly limited. Practically the only indication for 
operative interference, in the active period of sympathetic 
ophthalmitis, is long-continued high tension ; and in the 
foregoing pages the warning has been repeatedly uttered, 
that any operative meddling with the iris in this period 
is more apt to aggravate the process than to alleviate it ; 
and that, even if tension be relieved by an iridectomy, 
it soon becomes high again, owing to fresh plastic exu- 
dation. 

Should it seem imperatively necessary to endeavour to 
reduce a long-continued high tension, sclerotomy is to be 
preferred to iridectomy. It may have a beneficial effect, 
and is not likely to do harm. It can be repeated more than 
once, should it be deemed necessary. 

Paracentesis of the cornea is a measure which can be 
used as a temporary means of relief for high tension, and 
it, too, may be repeated. 

Optical Operations used in Sympathetic Ophthal- 
mitis. — The object of these operations is to provide an 
artificial pupil in the sympathising eye after all inflamma- 
tion, or tendency to it, has ceased, in order to improve, or to 
restore, vision which is interfered with by closure of the 



390 



DISEASES OF THE EYE. 



[CHAP. XI. 



pupil. Similar operations may be indicated occasionally in 
the exciting eye, in cases where it has not been excised. 

The cardinal point to be borne in mind, it may again be 
stated, is, that these operations must never be performed 
until six months at least have elapsed — and a longer period 
is preferable — after all and every tendency to inflammation, 
or irritation, has subsided. Inattention to this rule will 
result in a re-lighting of the inflammation, re-closure of the 
pupil which may have been made, or intraocular haemor- 
rhage, and a long period of waiting before any further 
operation can be undertaken, or else the globes may become 
shrunken, and all hope may be at an end. 

Moreover, as, even under the most favourable conditions, 
and with the most skilful operation, inflammation may 
return, or intraocular haemorrhage may occur, or the 
eye may become phthisical, no operation should be done 
unless the advantage to be gained from it, if successful, 
promises to be considerable. 

The three chief operations, one or other of which may be 
applicable, are : — Iridectomy, extraction of the clear or 
cataractous lens — for the lens is often cataractous from 
interference with its nutrition by reason of the irido-cyclitis — 
or discission of the cataractous lens. 

Iridectomy. — It is only exceptionally that iridectomy can be 
of use, in those eyes which have been the subjects of the severer 
plastic uveitis, resulting in total posterior synechia. In 
these cases, the tissue of the iris has undergone such extreme 
degeneration, that it is impossible to obtain more than mere 
shreds of the membrane with the forceps, so that a satisfactory 
coloboma can rarely be made. Or, if a fairly good coloboma 
be procured, it will probably be found that the pigmentary 
layer of the iris is left behind; and that this, with organised 
inflammatory products, lies on the anterior capsule, and 
obviates any gain that might have been derived from the 
coloboma. 



CHAP. XI.] 



THE UVEAL TRACT. 



391 



Iridectomy is indicated rather in those cases, where a less 
severe form of iritis has existed, resulting in a complete ring 
synechia of the pupillary margin only. Here a wide coloboma 
may often be made satisfactorily. The iris should be seized 
with the forceps at about the lesser circle. If seized at the 
pupillary margin, the intimate adhesion between the latter 
and the lens capsule may cause injury to the capsule, and 
consequent traumatic cataract. 

Extraction of the Lens. — This is indicated, if, on the 
formation of a coloboma, the lens be found to be cataractous, 
in those cases of ring synechia where iridectomy has been 
performed and the coloboma has closed again ; and in 
practically all cases of total posterior synechia, be the lens 
clear or opaque. In the former class of cases the ordinary 
combined method of cataract extraction answers the purpose, 
or a preliminary iridectomy may be made some weeks 
previously. 

Cases of total posterior synechia require a procedure. 
Such as one or other of the following: — 

WenzeVs Method. — The puncture, counter puncture, and 
incision are the same as in an ordinary cataract ex- 
traction, but the knife on entering is passed through 
cornea, iris, lens, iris, cornea. The lens is thus delivered 
as completely as possible, and out of the membrane com- 
posed of degenerated iris, retro-iridic connective tissue, and 
capsule, a V-shaped piece is cut with the forceps-scissors. 
The traumatism of this operation is great, and not every 
globe will bear it, and phthisis bulbi may follow. 

// />.«•<•/,/,• ,v/.,- .]f///i, )d. — An incision is made with, a keratoma 
in the lower margin of the cornea. With a fine capsule 
forceps, introduced into the pupil, the thickened anterior 
capsule is seized and drawn away and, by inserting a spatula, 
as much of the lens as possible is extracted. Some weeks 
later the pupillary membrane, composed of lenticular remains, 
posterior capsule, and inflammatory products, is divided with 



DISEASES OF THE EYE. 



[chap. xi. 



a cystotome. In this operation it is an advantage that 
the iris is not interfered with. 

Discission. — This operation was employed by the late 
Mr. George Critchett with success, in some cases where 
cataract was the main obstruction to sight. A discission 
needle is passed, by a boring motion, through the lenticular 
capsule ; another needle is then passed in close to the first, 
and by separating one point from the other a rent is made. 
This is followed generally by the escape into the anterior 
chamber of a small quantity of cheesy lens matter, which 
becomes gradually absorbed, and in the course of some 
weeks the capsule closes again. The operation has to be 
repeated several times before a clear pupil is obtained, 
care being taken that all irritation from the previous 
operation has subsided before another be undertaken. The 
chief danger in this operation is irritation and high tension, 
from swelling of the lenticular masses in the disorganised 
eye. 

Pathogenesis- — The pathogenesis of sympathetic ophthal- 
mitis is still obscure. There are two chief theories, each 
of which relies on infection by a specific micro-organism 
introduced into the exciting eye at the time of the injury, 
and which passes from it to the sympathising eye. But 
these theories differ from each other in respect of the path 
by which they would make the micro-organism pass from 
the first to the second eye. According to one theory the 
path is by the lymphatics of the optic nerve of the exciting 
eye, or its sheaths, then by the optic commissure, and optic 
nerve of the sympathising eye— in short, by direct continuity, 
as erysipelas extends over the skin. According to the 
other theory — which recent investigations seem to render 
the more probable of the two — micro-organisms enter the 
bloodvessels of the first eye, and are carried by the blood- 
stream through the body, but are pathogenetic only for 
the uveal tract of the second eye. 



chap, xi.] 



THE UVEAL Til ACT. 



393 



Pathology. — Hitherto the specific micro-organism of 
sympathetic ophthalmitis has evaded detection by every 
method. Quite recently Zur Nedden has discovered a pseudo 
diphtheritic-like bacillus in the blood of a patient suffering 
from sympathetic ophthalmitis, and which may be the 
micro-organism in question. The inflammatory products, 
both in the exciting and in the sympathising eye, are of 
twofold nature: — 1. A tough organised connective tissue 
containing few nuclei, which is developed on the surfaces 
of the iris, ciliary body, and retina. 2. An infiltration of 
the stroma of the uveal tract with lymphocytes, epithelioid 
cells, and giant cells (Fuchs). This second product of in- 
flammation is held by Fuchs to be the result of infection by 
the specific micro-organism which causes sympathetic ophthal- 
mitis, while he regards the connective tissue development 
as an accidental complication, due to infection by simultaneous 
entrance into the injured eye of another micro-organism. 
The clinical appearances and symptoms are due as much to 
the one as to the other product, and it cannot be known in 
any given case whether the essential product of the specific 
micro-organism be present in the first eye. 

Injuries of the Uveal Tract. 

Injuries of the Iris. — Punctured Wounds of the cornea, 
or of the corneo-scleral margin, frequently implicate the iris, 
but rarely do so without also injuring the crystalline lens 
or ciliary body, on which then the chief interest centres, as 
being the organs from which serious reaction is most likely 
to emanate. A small simple incised wound of the iris is 
not of great importance, for inflammatory reaction is not 
common, and any extravasation of blood at the seat of the 
iris wound, or into the anterior chamber (hyphrema) becomes 
absorbed, while, in most cases, the functions of the iris will 
probably not be affected nor sight endangered. Nevertheless, 
as iritis does sometimes occur, it is desirable to use such 



394 



[chap. xr. 



measures as are calculated to prevent it, such as atropine, 
a bandage, and rest of the eye and general system. Even 
extensive wounds of the iris are not often, as such, associated 
with serious danger to the eye, although the loss of continuity 
in the iris never closes up. Where, for instance, the iris 
is cut in its entire width from ciliary margin to pupillary 
margin, the permanent result is a wide coloboma, the margins 
of which may be adherent to the corneal wound. When 
the iris is prolapsed in the corneal wound, every effort should 
be made to reduce it completely ; and, if this cannot be 
effected, it is necessary to abscise the prolapsed portion. 
Incarceration of the iris in the corneal cicatrix may lead 
to secondary glaucoma, cystoid cicatrix, secondary septic 
infection of the iris, etc. 

Foreign Bodies of small size, such as bits of steel or iron, 
may perforate the cornea and fasten in the iris, the puncture 
in the cornea closing rapidly, and possibly no aqueous humour 
being lost. It is necessary always to remove such a foreign 
body without delay, although for some time it may cause no 
reaction. An incision should be made with a Grasfe's knife 
at the margin of the cornea, corresponding to the position of 
the foreign body, and the portion of iris containing the foreign 
body is then removed with forceps and scissors. 

Blows on the Eye are apt to cause, in addition to 
haemorrhage into the anterior chamber from the iris or from 
the canal of Schlemm, one of several remarkable lesions of 
the iris, namely : — 

1. Iridodialysis 1 — i.e., separation of the iris from its attach- 
ment to the ciliary body, wlich is usually accompanied by 
considerable hyphema. As much as one-half of the cir- 
cumference of the iris may be involved in the lesion ; or 
the latter may be so small as to be diagnosed only by the 
presence of the resulting small fresh hamiorrhage near 



i'pts, faAXvais, a separating. 



CHAP. XI.] 



THE UVEAL TRACT. 



395 



the ciliary margin of the iris ; or, after this has become 
absorbed, by aid of light transmitted to the eye by the 
ophthalmoscope, when no' alone the physiological pupil, 
but also the minute marginal traumatic pupil will be illu- 
minated. It is rarely that there is more than one dialysis. 
In certain degrees of the detachment, by reason of the 
sphincter of the iris having lost its fixed point, it becomes 
stretched in a straight line (Fig. 151) at the part corresponding 
to the dialysis, and assumes a D shape ; or if the detachment 
be more extensive, the pupil becomes kidney- shaped ; or the 
detached portion may entirely cover the pupil. The detached 
portion, too, may be turned on itself (anteflexion of the iris), 
the uveal surface being to the 
front. The functions of the 
eye after such an injury, even 
when extensive, are sometimes 
but little disturbed, or there 
may be monocular diplopia. 

It is stated that iridodialysis 
does not become re-attached ; but 
a case has come under the notice of one of us in which a 
very minute iridodialysis was healed, and another such 
case is recorded. The lengthened use of atropine is the 
most likely way in which to promote such a result, but it 
can only be hoped for if the iridodialysis be not extensive, 
and if the case be seen early. 

Iridodialysis does not increase in extent in the course 
of time, nor lead to further mischief in the eye. 

* 2. Retroflexion of the Iris. — From a blow on the eye the 
whole, or more commonly a portion, of the iris in its entire 
width can be folded back on the ciliary processes, giving 
the appearance of a very dilated pupil, or of a colobonia 
produced by a wide and peripheral iridectomy. In a true 
ooloboma the ciliary processes would be easily seen, but 
riot so in retroflexion, for the processes, being covered by 




396 



DISEASES OF THE EYE. 



[chap. XI. 



the retro flexed iris, present a smooth surface. A slight 
dislocation of the lens in the direction away from the iris 
lesion is often observed. Hetroflection of the iris cannot 
be cured, but useful vision is retained, if the injury be 
uncomplicated. 

* 3. Rupture of the Sphincter Iriclis. — There are not many 
cases of this lesion recorded. There may be but one 
rupture, or there may be a number of small ruptures 
distributed round the pupil. They show themselves as small 
triangular gaps in the pupillary margin, their bases directed 
towards the latter. This condition is also incurable, and 
some permanent disturbance of vision clue to the mydriasis 
results. 

* 4. Dehiscence of the Iris between the pupillary and ciliary 
margins. This is a slit-like rupture of the iris, which runs 
in a radial direction through the whole width of the iris, 
with the exception of the sphincter. The diagnosis sometimes 
cannot be made with certainty until, after a few days, the 
blood-clot covering the dehiscence is absorbed. The opening 
may be caused to close by the use of a myotic, which, by 
contracting the sphincter, brings the edges of the dehiscence 
together. 

* 5. Traumatic Aniridia. — The whole iris is torn from its 
ciliary insertion, and may be found lying in the anterior 
chamber or under the conjunctiva, having in the latter case 
passed through a rent at the corneo-scleral margin. Not 
only does the anterior chamber contain blood, but the 
vitreous humour is often infiltrated with haemorrhage. 
When the extravasated blood has become sufficiently 
absorbed, the absence of the iris will be noted, and in many 
instances the ciliary processes will be visible. If these 
latter are visible, the diagnosis ' aniridia ' can be definitely 
made, but cases do occur in which, notwithstanding the 
absence of the iris, the ciliary processes are not visible, 
owing probably to changes in the processes which cause 



CHAP. XI.] 



THE UVEAL TRACT. 



397 



them to shrink. Such cases then are difficult to distinguish 
from retroflexion of the iris, but the importance of the 
diagnosis is not great. 

G. Traumatic Mydriasis, and Myosis. — Of these, mydriasis 
is the more common. The dilatation is of medium degree, 
and the pupil is usually of irregular shape — oval, pear-shaped, 
or more dilated at one part than elsewhere — and contracts 
but slightly, or not at all, to light. Paralysis of accommodation 
usually accompanies traumatic paralysis of the sphincter 
iridis. The mydriasis is probably the result of concussion 
of the delicate nerve-endings in the sphincter of the iris. 
(See above, under Rupture of the Sphincter Iridis.) 
Traumatic mydriasis may recover after a long interval, but 
in most instances it remains as a permanent defect, with 
some derangement of vision due to it and to the paralysis 
of accommodation. 

With traumatic myosis there is apt to be spasm of 
accommodation, which may produce apparent myopia. The 
prognosis is fairly good. 

Treatment. — For mydriasis, protection spectacles, galvanism, 
and eserine. For myosis, atropine. 

Injuries of the Ciliary Body. — Punctured Wounds, and 
Foreign Bodies perforating the sclerotic at a distance of 
about 5 mm. around the cornea, are almost certain to 
implicate the ciliary body. If there be no prolapse of the 
ciliary body, nor any foreign body in the interior of the eye, 
the sclerotic wound may heal by aid of a bandage without 
further ill results. If a prolapse of the ciliary body or iris 
be present, it is to be abscised, with careful antiseptic 
measures ; and if the sclerotic wound be large, it may be 
thought desirable to unite its margins with sutures. 

Wounds of the ciliary body are apt to cause cyclitis, 
especially if the former be incarcerated in the sclerotic 
wound in healing, for the incarcerated portion is liable to 
become infected. 



398 



DISEASES OF THE EYE. 



[chap. XI. 



* Injuries of the Chorioid. — Small Foreign Bodies may 
pierce the sclerotic, or the cornea and lens, and may lodge 
in the chorioid, and, if favourably situated, can then 
be detected with the ophthalmoscope, and always by the 
Rbntgen rays if of metal (see chap. xv.). These foreign 
bodies require operative removal by the magnet, if of steel 
or iron (see chap, xv.) ; or, if the foreign body cannot be 
extracted, the eyeball must be removed, to avert sympathetic 
ophthalmitis. 

Incised Wounds of the sclerotic very frequently involve 
the chorioid (see p. 344). 

Rupture of the Chorioid near the posterior pole of the 
eye is often produced by blows on the eye, and is seen with 
the ophthalmoscope as a whitish-yellow (the colour of the 
sclerotic) crescent some two or three papilla-diameters in 
length, and one papilla-diameter or so distant from the 
optic entrance, the concavity of the crescent being directed 
towards the latter. Immediately after the accident ex- 
travasated blood sometimes prevents a view of the rupture. 
Some chorioiditis may result ; but, when this passes away, 
good vision is frequently restored and maintained, provided 
detachment of the retina does not ultimately supervene from 
cicatricial contraction at the seat of the rupture. On the 
other hand, a scotoma in the field may be produced, and if 
the rupture be in the region of the macula lutea, serious loss 
of sight may be caused. 

Treatment. — Careful protection of the eye, and abstinence 
from use of it, with dry cupping at the temple for three 
weeks, or until it may be assumed that all inflammatory 
tendency has subsided. 

Blows upon the eye may cause Extravasation of Blood in 
the Chorioid. If small, these extravasations do not extend 
beyond the chorioid. But, in the case of copious extra- 
vasation, the haemorrhage is poured out from the cborioidal 
vessels between that coat and the sclerotic, lifting and 



CHAP. XI.] 



THE UVEAL TRACT. 



399 



bulging forward the chorioid ; or between the chorioid and 
retina, giving rise to a detachment of the latter ; and if 
the retina give way, the blood is poured out into the 
vitreous humour. Should there be no vitreous humour 
opacity, the extravasations in the chorioid can be seen with 
the ophthalmoscope as somewhat indistinct (owing to result- 
ing opacity in the overlying retina) small red spots, or 
large round red spots, darker in the centre than at the 
margin. That these hemorrhages are in the chorioid can 
be recognised from the fact that they lie behind the retinal 
vessels. The haemorrhages become slowly absorbed, and 
after a time, provided they have not ruptured the retina, 
useful vision may be restored. 

Treatment. — Complete rest in bed. Atropine. Bandage. 

New Growths of the Uveal Tract. 

*NeW Growths of the Iris. — Cysts. — These vary from a 
very small size to that which would fill the anterior chamber. 
They may have either serous or solid contents. The serous 
kind was held to result always from a trauma causing an 
anterior synechia, or otherwise shutting off a fold of the 
iris, which became distended into a cyst by accumulation 
of aqueous humour. A case, however, which was not pre- 
ceded by a trauma has come under notice at the Victoria 
Hospital. The cysts with solid contents (epidermoid elements) 
are believed to have their origin in an eyelash or morsel of 
epidermis, which may have made its way into the anterior 
chamber by occasion of a perforating corneal wound. All these 
cysts are sources of serious danger to the eye (irido-chorioiditis, 
glaucoma, etc.), and, it has been stated, may even be the cause 
of sympathetic ophthalmitis, and hence their removal is called 
for. This can be effected without much difficulty if the tumour 
be small, but if it have attained a large size the attempt 
H often unsuccessful. A long incision should be made in the 



400 



BIS EASES OF THE EYE. 



[chap. XL 



corneoscleral margin, and the cyst, along with the portion of 
iris to which it is attached, drawn out and cut off. 

Granuloma is the narue given to a benign neoplasm of 
the iris, of which the structure resembles granulation tissue. 
Clinically it is a small pale tumour, or there may be several 
such tumours, which gradually grow to fill the anterior 
chamber, rupture the cornea, and finally induce phthisis 
bulbi. It is held by some that these growths depend on a 
syphilitic taint, and by others that they are tubercular. 

Solitary Tubercle. — Solitary tubercle may be accompanied 
by a few smaller growths, but it generally begins as a single 
yellowish-white tumour, often without iritis, which gradually 
increases in size until it may fill the anterior chamber. It 
finally involves the cornea, which it perforates, forming a 
fungating mass, and this subsequently breaks down, leaving 
only a small shrunken globe in the socket. 

Treatment. — Tuberculin in the early stages, and if perfora- 
tion should take place excision of the eyeball 

Sarcoma. — Of the uveal tract, the iris is the portion most 
rarely affected with primary sarcoma. It arises usually 
from a congenital pigmented nsevus of the iris, and is 
commonly a melano-sarcoma ; but leuco-sarcoma has also 
been recorded. As the tumour increases in size, it fills the 
anterior chamber, and grows backwards into the ciliary 
body and into the canal of Schlemm. It is not usual for 
the tumour to become extraocular by growing through at 
the corneo-scleral margin, and in this respect it is unlike 
tubercle of the iris. Irritation or inflammatory symptoms 
are not often present, and secondary glaucoma doss not 
come ou until a later stage, when the growth has filled the 
anterior chamber, or involved the ciliary body extensively. 

Treatment. — Enucleation of the eye should be advised as 
soon as the diagnosis of sarcoma of the iris lias been made. 
There is naturally a desire on the part of the surgeon, 
when the tumour is small, to save the eye, which probably 



CHAP. XI.] 



THE UVEAL TRACT. 



401 



lias full vision, by excising the portion of iris in which the 
growth is seated, and there are some cases on record in 
w hich this was done, and where no recurrence of the tumour 
took place. But in adopting this conservative method, the 
surgeon accepts grave responsibility ; for it is not possible 
to determine clinically whether the sarcomatous growth is 
truly, or only apparently, confined to the limited region of 
the iris, where it can be seen. Even in the early stages 
of many cases of sarcoma of the iris, the neoplasm invades the 
ligamentum pectinatum, the canal of Schlemm, or the ciliary 
body ; so that, although the iris tumour be thoroughly 
removed, the growth reappears in the eye before long, 
while in the meantime risk of infection of the general 
system has been run. 

Carcinoma. — Two or three cases of metastatic carcinoma of 
the iris and ciliary body are on record, with the breast as 
the primary seat of disease. 

Ophthalmia Nodosa. — See p. 176. 

*New Growths of the Ciliary Body. — Sarcoma of 

the ciliary body is generally pigmented, and often passes 
unobserved, until it attains considerable size as a brown 
mass, which was at first concealed from view by the iris. 
Occasionally it is first noticed when it makes its appearance 
at the angle of the anterior chamber. It usually also grows 
backwards into the chorioid, and runs the same course as 
sarcoma of the chorioid, but in rare cases extends round the 
whole ciliary region (ring sarcoma). Ptemoval of the eye- 
ball should be urged, but is often for a time declined by 
the patient, as sight is but slightly affected in the early 
stages. 

.Myosarcoma originating in the ciliary muscle has been 
observed a few times. 

Carcinoma. — Secondary carcinoma may occur in the 
ciliary body as in the iris and the chorioid, but is very rare. 

'New Growths of the Chorioid. — Sarcoma is by far the 

26 



402 



DISEASES OF THE EYE. 



[chap. XI. 



most common neoplasm of the chorioid, and the chorioid is 
the most common seat of ocular sarcoma. It is seen at all 
times of life, but most frequently between the ages of forty 
and sixty. Both melano-sai-coma and leuco-sarcoma occur, 
and may originate in any part of the chorioid. 

If seen in a very early stage, it is easily recognised from 
its projecting over the general surface of the fundus, the 
retina lying closely applied to it ; but, unless it be in the 
region of the macula lutea, it may not cause any serious 
disturbance of vision, and hence may not at that period be 
brought under the notice of the surgeon. The diagnosis 
from detachment of the chorioid at this stage is made by 
the presence in the latter condition of the characteristic 
chorioidal vessels, and by the peculiar colour of the chorioid. 
Detachment of the chorioid, too, is much rarer than sarcoma. 

The new growth soon gives rise to detachment of the retina, 
by reason of serous exudation from the chorioid; and this 
may be accompanied by opacity in the vitreous humour, 
which contributes in rendering the diagnosis with the 
ophthalmoscope difficult or impossible. If the detachment be 
shallow and the retina translucent, the tumour may still 
sometimes be seen through the sub-retinal fluid by aid 
of strong illumination ; and even direct sunlight may be 
employed in some such cases. Often the detachment com- 
mences at a part of the fundus not immediately over the 
tumour, but some distance removed from it. Owing to the 
great, and often sudden, defect of vision which comes on in 
this stage, we very commonly see these cases now for the 
first time. The history of the case may aid us ; while the 
absence of the more usual causes of detachment of the retina 
should make us suspicious of an intraocular tumour, and the 
fundus should be carefully examined, with dilated pupil, in 
all such cases. 

At this and at later stages, Leber's Sclerotic Trans- 
illuminator (Fig. 152, ^ size) is a valuable diagnostic aid. It 



CHAP. XI.] 



THE UVEAL TRACT. 



403 



consists of a small electric lamp (b), which requires a current 
of eight to ten volts, enclosed in a metal jacket (a). The 
anterior end of the lamp is in contact with a short glass 
rod (c) covered with a hard rubber sheath. The light of 
the lamp is transmitted along the glass rod, and the exposed 
end (d) of the latter is placed on the sclerotic of the 
cocainised eye, in a dark room. 



Then, if the eye be normal, or 
even if a ripe cataract be 
present, the pupil lights up 
with the familiar red glow 




from the chorioid. But if, b j 

internal to the spot at which 
the glass rod is applied, a new A 
growth be present, the pupil S 
does not light up — it remains ■ 
dark. By slipping the rod Fig. 152. 

over the whole of the suspected 

region, or as much of it as can be reached, or, indeed, 
over the whole exposed sclerotic, it can be ascertained 
whether an intraocular growth be present. The only 
limitation to the method is in those cases where the tumour 
is situated much behind the equator, a region in which the 
rod cannot be brought in contact with the sclerotic. 

Soon the intraocular tension increases. This makes the 
diagnosis again more easy in many cases, for the combination 
of detached retina and increased tension exists only with intra- 
ocular tumours. The increased tension may come on very 
slowly, and without ciliary neuralgia ; or more rapidly, and 
with all the signs and symptoms of acute glaucoma. Yet, 
if the case come under observation now for the first time, 
the diagnosis may be by no means easy, should the refracting 
media be opaque (as always in acute glaucoma), and con- 
sequently the detachment of the retina concealed from view. 
Here, again, the history of the case is all we have to 



404 



[chap. XI. 



depend on, especially the fact of the patient having noticed 
a defect at one side of his field of vision previous to the 
onset of glaucoma. 

In the next stage of the growth it perforates the cornea or 
sclerotic, and, increasing rapidly in size, although still covered 
with conjunctiva, it pushes the eyeball to one side, the upper 
lid being stretched tightly over the whole. On raising the lid 
the tumour is seen as a bluish-grey mass with irregular surface. 
The conjunctiva is now soon perforated, and the surface of 
the tumour becomes ulcerated, with a foul-smelling discharge 
and occasional hemorrhages. The tumour gradually invades 
the surrounding skin and the bones of the orbit, and by 
extending through the sphenoidal fissure and optic foramen 
reaches the base of the brain. 

Another, and much less usual, course of chorioidal sarcomn, 
is that in which, without first perforating the cornea or 
sclerotic, the tumour sets up irido-cyclitis, leading to phthisis 
bulbi. Cases in which sarcoma of the chorioid was found 
in shrunken eyeballs have given rise to the view that such 
eyeballs are prone to develop sarcoma. While it is quite 
possible that sarcoma may develop in a shrunken eyeball, it 
is tolerably certain that, in the majority of the cases in 
which both diseases are present, the sarcoma is the primary 
disease, and undergoes more or less necrosis. 

Sarcoma of the chorioid very occasionally gives rise to 
sympathetic ophthalmitis (pp. 378, 383). 

It is usually upon the neighbouring tissues of the eyeball 
becoming involved that secondary growths begin to form iu 
other organs, the one most prone to be affected being the 
liver. The lungs, stomach, peritoneum, spleen, and kidneys 
may all be attacked. 

Chorioidal sarcoma is almost always primary, but it has 
been seen a few times as a metastatic disease. 

Cwciwoma. — This is extremely rare, and the cases of it on 
record were all of metastatic origin, the primary disease being 



CHAP. XI. J 



THE UVEAL TRACT, 



405 



in the breast. It is not possible to distinguish chorioidal 
sarcoma from chorioidal carcinoma by the ophthalmoscope. 

Tub&rcU is sometimes seen in cases of acute miliary 
tuberculosis as round, slightly prominent, pale yellowish 
spots, of sizes varying from 0"5 to 2 - 5 mm. in diameter, 
situated always in the neighbourhood of the optic papilla 
and macula lutea, and unaccompanied by pigmentary or other 
chorioidal changes. There may be bat one of these tubercles, 
or there may be many of them. When they occur, it is, as 
a rule, in a late stage of the general disease, but they have 
occasionally been noted long before its appearance. In 
obscure cases of the general disease, the ophthalmoscope has 
sometimes rendered valuable diagnostic aid by discovering 
these minute tubercles in the chorioid. 

Very rarely does a tubercular tumour grow in the chorioid 
in cases of general chronic tuberculosis, attaining to a 
large size, and destroying the eye similarly as sarcoma 
or carcinoma. In young children it may be impossible to 
diagnose between a tubercular tumour of the chorioid and 
a glioma of the retina (chap. xvi.). Yet, as in either case 
enucleation is indicated, the diagnosis is not of much practical 
importance. 

Other, but rare, forms of tumour of the chorioid are : — ■ 
Sarcoma G'arcinomatosiim, Osteo-Sarcoma, and Lymphoma. 
Treatment. — So long as, in cases of sarcoma and carcinoma, 
the tumour is wholly intraocular, enucleation of the eyeball 
should be performed, and may be done with fair hopes of 
saving the patient's life, if the disease be primary. When 
the orbital tissues have become involved, extirpation of all 
the contents of the orbit, and even, if necessary, removal of 
portions of its bony walls, ought to be undertaken, should 
the general health permit, in order to rid the patient of 
his loathsome disease ; although the probable presence of 
secondary growths elsewhere renders but small the prospect 
of saving the patient's life. 



406 



DISEASES OF THE EYE. 



[chap. XI. 



Cases of miliary chorioidal tubercle do not call for direct 
treatment. 

In cases of tubercular tumour the question of removal 
of the eyeball must depend upon the general state of the 
patient ; but, if it seem probable that life will be prolonged 
until after the ocular growth would have become extra- 
ocular, removal of the eye should be recommended. 

*0ther Diseases of the Chorioid. — Posterior Sclero- 

Chorioiditis, or Posterior Staphyloma. — This condition is 
described in connection with myopia (p. 54), which is its 
almost constant cause. 

Detachment of the Chorioid. — As the result of copious loss 
of vitreous, during operations, or from injury, detachment 
of the chorioid is not uncommon, but it does not require to 
be specially diagnosed in these instances, and therefore it is 
not important to consider it further here. 

Idiopathic detachment of the chorioid is extremely rare. 
Its ophthalmoscopic appearances are apt to be taken at 
first sight for a simple detachment of the retina, or for 
leuco-sarcoma ; but on closer inspection the chorioidal 
stroma is observed to lie immediately behind the detached 
retina, and its vessels, etc., are seen in the upright image 
by aid of the same lens as are the retinal vessels. The 
chorioid is not everywhere detached, but is separated from 
the sclerotic in several different places, and these detach- 
ments are seen in the form of apparently solid hemispherical 
protuberances rising abruptly from the fundus into the 
vitreous humour. In other places the chorioid is in contact 
with the sclerotic, although in some of these positions there 
may be detachment of the retina alone. The vitreous 
humour is more or less opaque. Vision is greatly lowered 
or quite destroyed. 

It is probable that a chronic chorioido-retinitis has been 
an antecedent condition in all of these cases. Indeed, there 
often are signs of old retinitis present, such as perivasculitis 



CHAP. XI.] 



THE UVEAL TRACT. 



407 



and connective tissue striation ; and in one case a retinitis 
was actually observed long before the detachment of the 
chorioid came on. Adhesions between the chorioid and 
sclerotic are formed in consequence of this inflammation ; and 
then inflammatory exudation takes place behind the chorioid, 
and separates it from the sclerotic, where it is not adherent 
to the latter. 

The process ends either in phthisis bulbi, in consequence 
of vascular changes and disturbances of nutrition, or in cure 
of a certain degree, in so far as by absorption of some of the 
exudation, and by alteration of the remainder of it into 
connective tissue, a return of the chorioid and retina to 
their normal position is rendered possible ; but even then 
restoration of sight, with tissues so disorganised, cannot be 
looked for. 

Treatment hitherto seems to have been of no avail. Pro- 
bably active mercurialisation might afford the best chance of 
doing good, should a case come under notice. 

Fuchs has pointed out that detachment of the chorioid 
occurs in a good many cases of cataract extraction some 
days after the operation, although there has been no 
loss of vitreous, and also in some cases of iridectomy. 
It can often be found with the ophthalmoscope, and 
even sometimes with the oblique illumination, in those 
cases of cataract extraction in which the anterior chamber 
has not formed, or in which, having formed, it has 
become empty again. It is mainly after iridectomy for 
chronic simple glaucoma that chorioidal detachment has 
been noticed. The probable explanation is, that a slight 
aperture of communication has been made between the 
anterior chamber and the sub-chorioidal space, through 
which the aqueous humour passes behind the chorioid. 
With the re-establishment of the anterior chamber, the 
chorioidal detachment goes back, and the prognosis is in 
all cases good as regards vision. 



408 



DISEASES OF THE EYE. 



[CHAP. XT. 



* Centred Senile Areolar A trophy of the Chorioid — This is 
not a very rare disease, and presents the appearance of a 
white patch, often of considerable extent;, at and around the 
macular region. In some cases a hemorrhage in the chorioid 
and posterior layers of the retina forms the starting-point 
of the disease. The retinal functions always suffer much ; for 
an absolute central scotoma is produced, which renders read- 
ing and writing impossible, although locomotion is not greatly 
impeded, as the periphery of the field remains intact. The 
discovery of the presence of this disease, after a cataract has 
been successfully removed, is sometimes a source of intense 
disappointment both to patient and surgeon, which cannot be 
guarded against unless the condition of the fundus oculi have 
been noted while the cataract was still incipient. 

Treatment is of no avail, but absolute rest of the eyes from 
all attempts at near work, and the use of dark protection 
spectacles are important, so that, at the least, the advance 
of the disease may not be encouraged. 

Malformations of the Uveal Tract. 
*Malformations of the Iris. — Heterophthalmos (eVepo?, 

different; d<j>6a\fi6<;). — This term indicates that the colour 
of the iris in one eye is different from that in the other. 

Corectopia (icopr), the pupil; eicTOiros, out of position), or 
malposition of the pupil. The pupil sometimes occupies a 
position farther from the centre of the iris than normally. 

Polycoria (ttoXvs, many ; Koprj, the pupil). — Where there 
is more than one pupil. The supernumerary pupil may be 
separated by only a small bridge from the normal pupil, or 
it may be situated very near the periphery of the iris. In 
neither case has it a special sphincter. 

Persistent Pupillary Membrane appears in the form of 
very fine threads stretched across the pupil. They cannot 
be mistaken for posterior synechia?, as they are attached 



CHAP. XI.] 



THE UVEAL TRACT. 



409 



to the anterior surface of the iris some distance from the 
margin of the pupil. They do not interfere with the motions 
of the pupil, nor with vision. 

( 'oloboma (/coAo/369, maimed) and Irideremia (Ipis, the iris ; 
iprjfjLia, want of). — These two defects have been shown hy 
Treacher Collins to he due to a similar cause— in short, that 
they are different degrees of one and the same condition. 
Before the iris is formed in the foetus there exists, between 
the posterior surface of the cornea and the anterior capsule 
of the lens, the anterior poi-tion of the fibro-vascular sheath. 
This receives its blood-supply partly from the ciliary arteries, 
and partly from those in the posterior fibro-vascular sheath, 
prolonged round the sides of the lens to join it. The cornea, 
anterior fibro-vascular sheath, and lens lie in close contact 
with each other. The iris is developed by growing forwards 
from the margin of the anterior chamber, and in doing so 
has to insinuate itself between the cornea and anterior 
fibro-vascular sheath on the one side and the lens on the 
other, pushing the prolongation from the posterior fibro- 
vascular sheath in front of it. The anterior fibro-vascular 
sheath subsequently becomes the pupillary membrane, of 
which portions sometimes persist (see above). If we suppose 
some abnormal adhesion to occur between the cornea, 
anterior fibro-vascular sheath, and lens-capsule, or some 
delay in their separation at the whole circumference of 
the future anterior chamber, we can understand how a 
mechanical obstruction to any growth of the iris forwards 
would be introduced, resulting in complete absence of the 
iris, or irideremia. If the obstruction be confined to a portion 
only of the anterior chamber, the corresponding portion only 
of the iris will be prevented from growing forwards, and the 
result will be one or more congenital colobomata. Irideremia 
may be complete or partial. In the latter case it may be 
the inner circle only which is wanting, giving the pupil the 
appearance of dilatation with atropine. Where the entire 



•110 



DISEASES OF THE EYE. 



[chap. xr. 



iris is absent the ciliary processes can be seen all round. 
The condition may be binocular. The patients suffer chiefly 
from dazzling by light, from which either protection or 
stenopeic spectacles afford some relief. 

*Malformations of the Chorioid. — Coloboma. — This is a 

solution of continuity occurring always in the lower part 
of the chorioid, and usually associated with a similar defect 
in the iris. It may commence at the optic papilla, and 
involve the ciliary body also, and even the crystalline lens 
may have a corresponding notch ; or it may not extend so 
far in either direction. The condition is recognised ophthal- 
moscopically by the white patch, due to exposure of the 
sclerotic where the chorioid is deficient. Sometimes the 
retina is absent over the defect in the chorioid, a circumstance 
which may be ascertained by the arrangement of the retinal 
vessels ; but, even if it be present, its functions at that place 
are wanting, and a defect in the field of vision exists. Central 
vision is often normal. 

Albinismus, or the want of pigment in the chorioid and 
iris. This is usually accompanied by defective pigmentation 
of the hair of the body. The iris has a pink appearance, due 
to reflection of light from its blood-vessels, and from those of 
the chorioid, and with the ophthalmoscope the latter vessels 
can be seen down to their finest branchings. The light 
which enters the eye, not being partially absorbed by 
pigment, causes the patient much dazzling, and high degrees 
of the condition are usually accompanied by nystagmus. In 
childhood the albinismus and attendant symptoms are more 
marked than later in life, when some degree of pigmentation 
usually takes place. 

Much advantage may be derived in many of these cases by 
the use of stenopaaic spectacles, at least for near work. Any 
defect of refraction should be carefully corrected, in order 
to give the patients the best possible use of their eyes. 



CHAP XI.] 



TEE UVEAL TRACT. 



411 




■112 



DISEASES OF THE EYE. 



[chap. XI. 



in zonular cataract, corneal opacities, or closed pupil ; to 
reduce abnormally high intraocular tension, in primary and 
secondary glaucoma ; and for the removal of tumours or 
foreign bodies in the iris. 

The instruments required are a spring speculum ; a 
fixation forceps, with spring catch (Fig. 157) ; a lance-shaped 
iridectomy knife (keratome) (Fig. 153), or a Graefe's cataract 
knife ; a bent iris forceps (Fig. 154), or a Tyrrell's hook 
(Fig. 155) ; an iris scissors curved on the flat (Fig. 156), or 
a de Wecker's forceps-scissors ; and a small spatula. 

The width of the coloboma depends a good deal on the length 




Fig. 157. 



of the corneal incision, for it cannot be wider than the in- 
cision is long. Its depth depends on the proximity of this 
incision to the corneo-scleral margin. If a wide and very 
peripheral coloboma be desired, the incision must be long, 
and must lie actually in the corneo-scleral margin ; the iris 
forceps being then introduced, a portion of the iris corre- 
sponding to the length of the incision may be seized, drawn 
out, and cut off, the blades of the scissors being applied 




Fig. 158. Fig. 159. FiG. 1G0. 



parallel, and close to the incision, and by this means a 
coloboma, as at Fig. 158, is produced. An incision some- 
what inside the corneal margin will give a pupil, as in 
Fig. 159. A narrow coloboma (Fig. 160) is obtained by a 



CHAP. XI.] 



THE UVEAL TRACT. 



413 



short corneal incision, which may be more or less peripheral 
as circumstances require ; by taking up as little as possible 
of the iris in the forceps, or by using a Tyrrell's hook, 
instead of an iris forceps, for catching and drawing out 
the iris ; and by applying the blades of the scissors at 
right angles to the incision in the corneal margin. 

In glaucoma a wide and very peripheral coloboma is 
required. For optical purposes a narrow iridectomy is 
required, because with a wide coloboma the diffusion of 
light may be very troublesome to the patient. 

The best position for an iridectomy for glaucoma is in 
the upper quadrant of the iris, as there the subsequent 
dazzling by light and the disfigurement are least. But 
the position, by preference, for an optical pupil is below 
and to the inside, being that most nearly in the direction 
of the axis of vision. If, however, this position be occupied 
by a corneal opacity, the coloboma should be made directly 
downwards ; or, if that place be ineligible, then downwards 
and outwards, or directly downwards, or directly inwards. 
The upward positions are not satisfactory for optical pupils, 
owing to the overhanging of the upper lid ; yet it often 
happens that we have no other choice. 

In the Performance of an Iridectomy, the eye should be fixed 
with a forceps at a position on the same meridian as that 
in which the coloboma is to lie, but at the opposite side of 
the cornea, and close to the latter. The point of the lance- 
shaped knife is then to be entered almost perpendicularly to 
the surface of the cornea, and made to penetrate the latter. 
As soon as the point of the blade has entered the anterior 
chamber, the handle of the knife is lowered, and the blade 
is passed on into the anterior chamber in a plane parallel to 
the surface of the iris, until the incision has attained the 
required length. The handle of the knife is now lowered still 
more, so as to bring the point of the blade almost in contact 
with the posterior surface of the cornea, in order to prevent any 



414 



DISEASES OF THE EYE. 



[chap. XI. 



injury to the lens in the next motion. The knife is then very 
slowly withdrawn from the anterior chamber. At the same 
time the aqueous humour flows off slowly, and the crystalline 
lens and iris come forwards. The fixation forceps is now taken 
over by the assistant, and the bent iris-forceps is passed 
closed into the anterior chamber, its points directed towards 
the posterior surface of the cornea, so as to avoid engaging 
them in the iris. When the pupillary margin has been 
reached, the forceps is opened as widely as the corneal incision 
will permit, and the corresponding portion of the iris is seized 
and drawn out to its full extent through the corneal incision. 
With the scissors held in the other hand the exposed bit of 
iris is snipped off quite close to the corneal incision. Care 
should now be taken that the angles of the coloboma do not 
remain in the wound ; and, if they are seen to do so, they 
must be reposed by stroking the region of the incision with 
a hard rubber spoon, or by pushing them into then - places 
gently with the spatula. 

Iridotomy. — For description and uses of this operation 
see chap. xiv. 




CHAPTEE XII. 

THE PUPIL.' 

The movements of the iris, which produce contraction and dilatation 
of the pupil, are governed by two unstriped muscles — namely, the 
sphincter pupillse, and the dilator pupillre. The sphincter is a ring of 
muscle situated close to the margin of the pupil and is supplied by 
the third nerve, while the dilator is a thin muscular layer, of which 
the fibres are arranged radially, and which is situated near the posterior 
surface of the iris, and is supplied by the sympathetic nerve. 

As the iris muscles are not under the control of the will, they are 
set in motion either by reflex stimuli, or by what Parsons aptly terms 
synkinesis — i.e., by association with other voluntary or involuntary 
movements. 

Contraction of the Pupil is brought about by the light reflex, or by 
the accommodation synkinesis. 

The Light Beflex depends upon the transmission of the stimulus 
fpjm the retina, by the afferent path to the pupil constricting centre 
of the third nerve nucleus in the floor of the Aqueduct of Sylvius, 
and thence by the efferent third nerve path to the sphincter pupillre. 
As regards the afferent path, it has been ascertained that the optic 
nerve contains fibres of two different calibres, and it is held that the 
finer fibres are afferent pupillo-constrictor, the coarser fibres being 
the visual fibres. The pupillary fibres undergo partial decussation 
in the optic commissure, and pass into the optic tracts. They leave 
the tract before it reaches the external geniculate body, but at what 
point, and their further route to the third nerve nucleus, are not 
certainly known. It is on the whole probable that the path taken 
is by the superior brachium to the superior quadrigeminal body, and 
thence by new connections to the third nerve nucleus of the same 
and of the opposite side. The portion of the third nerve nucleus 
which gives origin to the pupillo-constrictor fibres is the Edinger- 
VVestphal nucleus, situated in the median part of the main nucleus. 



1 For much of the physiological portions of this chapter the authors 
are indebted to Mr. J. Herbert Parsons' ' Arris and Gale Lectures,' 190). 

415 



416 



DISEASES OF THE EYE. 



[chap. xii. 



The efferent pupillo-constrictor path is contained in the trunk of the 
third nerve. In the orbit the pupillo-eonstricting fibres pass into the 
branch which supplies the inferior oblique, and leave it again by the 
short root of the ciliary ganglion. Prom this ganglion the sphincter 
nerve filaments — the short ciliary nerves — pass to the eyeball, pierce 
the sclerotic around the optic nerve, and pass on the inner surface of 
the sclerotic to the iris. The innervation of the ciliary muscle (the 
muscle of accommodation) is from the same source. 

The Accommodation Synkinesis is contraction of the pupil associated 
with accommodation, or more strictly with convergence of the optic 
axes. The act of accommodation of the eye for near vision is intimately 
bound up with the act of convergence of the optic axis, which takes 
place simultaneously with accommodation (see p. 26), and it can be shown, 
that if, experimentally, accommodation and convergence be dissociated, 
it is possible to accommodate without producing contraction of the pupil, 
but not to converge the optic axes without that synkinesis. Hence it 
is really with the act of convergence, not with the act of accommodation, 
that contraction of the pupil is associated. The object of this 
contraction is to cut off rays which would fall on the peripheral 
portions of the lens, portions which are not curved in the change for 
accommodation in the same degree as is the centre of the lens. 

Engorgement of the bloodvessels of the iris, as in hyperemia, or 
inflammation, or following paracentesis of the anterior chamber, is 
a third influence which causes contraction of the pupil. 

Dilatation of the Pupil. — The nerve supply of the dilator pupills 
is from the cervical sympathetic. The path originates near the third 
nerve nucleus, and passes through the medulla to a region, in the upper 
dorsal and lower cervical portion of the lateral column of the spinal 
cord, called the cilio-spinal centre. The path leaves the cord by the 
central roots of the first three thoracic nerves, and thence, by way of 
the rami communicantes, passes on to the first thoracic ganglion. 
Thence into the anterior and posterior limbs of the annulus of 
Vieussens and by the cervical sympathetic to the superior sympathetic 
ganglion, from whence the path enters the skull by the cervico- 
gasserian fibres to reach the gasserian ganglion. From this ganglion 
it passes to the ophthalmic division of the fifth nerve by its nasal 
branch, and then, leaving it, it joins the long ciliary nerves which 
enter the eye around the optic nerve, and reach the iris by passing 
forwards between sclerotic and chorioid. It seems probable, however, 
that all the dilating fibres do not run to the eye by way of the cervical 
sympathetic, and that the gasserian ganglion receives pupil-dilating 
fibres from the sympathetic traversing the cavum tympani. Dilatation 
of the pupil is brought about by the sensory reflex, or by the cerebral 
synkinesis. 

The Sensory Keflex can be induced by almost any sensory stimulus 



CHAP. XII ] 



THE PUPIL. 



417 



— e.g., the prick of a pin or a pinch on the nack, galvanism applied 
to the leg, the tickling of a sensitive place in the region of the fifth 
nerve on ths face, etc. Westphal observed dilatation on shouting 
loudly into the ear of a person under chloroform. Schiff and Foa 
found that in curarised dogs and cats a dilatation took place on the 
application of ever)' stimulus, not necessarily painful, applied to the 
nerves of common sensation in any part of the body. Indeed, it is 
not necessary in the human subject that the stimulation should pro- 
duce any sensation, for stimulation of the skin of the affected side in 
hemianesthesia, as also in sleep and in coma, will find response in 
dilatation of the pupil. The afferent impulses, in the case of nerves 
of common sensation, reach the cilio-spinal centre by way of the 
posterior spinal columns. 

The Cerebral Synkinesis is induced by psychical emotions. The pupils 
of a cat in anger dilate, and those of a frightened child. In sleep, or 
when under the complete influence of an anaesthetic, the pupils are 
contracted, for then all psychical and sensitive stimuli are reduced to a 
minimum. Facts authorise the conclusion that the medium dilatation 
of the pupil in the healthy state depends chiefly on the intensity of 
these stimuli, habitually transmitted through the sympathetic. If in 
any individual they be slight, his pupil is contracted ; if intense, it is 
dilated. In delicate, nervous, excitable people the pupils are often 
much, and habitually, dilated. 

In addition to those already mentioned, there are causes for the 
dilatation of the pupil, which can hardly be referred to simple reflex 
action, but which seem to be, like the contraction of the pupil on 
convergence of the visual lines, synkinetic with other centres in the 
medulla oblongata, especially with those for respiration and uterine 
action. With every deep inspiration or expiration a considerable 
pupillary dilatation takes place, not identical with that slight dilatation 
occurring on each ordinary inspiration, and depending on variation of 
blood pressure, but due to simultaneous stimulation of the respiratory 
and pupil-dilating centres by retention of carbonic acid gas in the 
blood. Marked dilatation at the beginning of each labour pain has 
been observed, and may be explained as an associated action of the 
neighbouring centres for uterine movements and pupil-dilatation. 

Hippus. In addition to the normal pupillary motions described in the 
foregoing, and visible for the most part to the naked eye of the observer, 
there is a phenomenon of pupillary motion, termed hippus, which is 
discoverable only by aid of a corneal microscope or loup, consisting in 
perpetual, but very minute and irregular, fluctuations in size of the 
pupil. It is due to the ever-varying sensitive and psychical reflexes 
which are thus constantly manifesting their influehces on the pupil. 

The reflex mobility of the pupil to light is tested most commonly for 
the purpose of deciding the existence or otherwise of posterior synechia}. 

27 



IIS 



DISEASES Ob' TEE EYE. 



[chap. xii. 



The next most common object of the test, is to determine the sensi- 
tiveness to light of the retina or of the visual centre. It affords 
generally a sufficient test of the presence or absence of quantitative per- 
ception of light: but the latter function may be wanting in certain 
diseased states, and yet the pupil-reflex take place ; or the pupil-reflex 
may be wanting, and still perception of light be present. The test is 
best performed in diffuse daylight, with the patient's Eace directed 
towards the window, a distant object beiu.g looked at, and the eye 
which is not under examination being carefully excluded from the light. 
The surgeon then, having observed the size of the pupil to be examined, 
excludes the eye from light with his hand for some moments. On 
removing the excluding hand, a normally reacting pupil will be found 
to have become dilated; and this dilatation, after an interval of about 
half a second, will be observed to give way to an extreme contraction, 
which is maintained only for a moment, and is then succeeded by a 
moderate dilatation, and the pupil then again contracts somewhat, 
and so on, until, after some further minute oscillations, it comes to a 
standstill. The explanation for this hippns is that each contrac- 
tion of the pupil, by diminishing the supply of light to the retina, 
contains in itself the cause of the succeeding dilatation ; and, for 
the converse reason, each dilatation sets a-going the succeeding 
contraction, until at last equilibrium is attained. A comparison be- 
tween the maximum of dilatation and maximum of contraction, along 
witli the promptness and rapidity with which the contraction takes 
place, enables the observer to form an estimate of the activity of the 
pupil-reflex. In performing this test it is important that the patient's 
gaze should be fixed all the time on a distant object — hence, unless 
where a mere trace of perception of light remains, the test used with 
the artificial light is not so reliable as that with daylight— so that the 
accommodation synkenesis may not vitiate the experiment. The 
consensual reflex of the pupil, as well as the direct, should always be 
tested— one eye being alternately excluded and exposed, the motions of 
the pupil of the other eye are observed and compared with those of 
its fellow. In examining the pupils we have also to decide whether they 
are of equal size ; and, in order to avoid error through posterior synechia, 
the comparison should be made, with both eyes open, successively in two 
very different brightnesses of light. Under normal conditions equality 
In size of the pupils will exist, not only with both eyes open, but also if 
one eye be shaded ; for the normal consensual pupil-reflex is equal to 
the direct reflex. If the pupils be found of different sizes, the least 
movable one is usually the pathological pupil ; but this question is 
often difficult to decide. Finally, it should bo noted whether the 
direct pupil-reflex is similar in all respects in each eye. 

Action of the Mydriatics on the Pupil. (See also p. 130.)— Solution of 
sulphate of atropine dropped into the conjunctival sac dilates the pupil, 



CHAP. XII.] 



THE PUPIL. 



419 



through absorption into the aqueous humour. For it has been shown 
that the aqueous humour of an eye into which atropine has been 
instilled acts as a mydriatic when dropped into another eye. It is 
evident that atropine acts, not merely by paralysing the sphincter 
papillae, but also by stimulating the dilator, inasmuch as in complete 
paralysis of the third nerve instillation of atropine produces a further 
dilatation of the pupil. If cocaine be combined with atropine in the 
solution, or if it be dropped in as a separate collyrium, a further 
dilatation of the pupil takes place. Whether this is to be referred to 
contraction of the blood-vessels of the iris, or to stimulation of the 
sympathetic supplying the dilator pupillas, is not clear. Scopolamine, 
homatropine, ephedrine, etc., act similarly to atropine. 

Action of the Myotics on the Pupil. (See also p. 422.)— These drugs 
— of which the chief are Eserine and Pilocarpine — act in all respects 
as the complete antagonists of the mydriatics, by stimulating the 
endings of the third nerve in the sphincter pupillse. Morphia, taken 
internally or used hypodermically, has an antagonistic effect to atropine, 
when it is absorbed into the system, and is employed as an antidote 
in cases of atropine poisoning. (See p. 358.) 



The three following tables, show the action of 

TABLE 
The -Mydriatics 



Solutions commonly used 



Effect on pupil 



Effect on accommodation 

Action — 

begins in 

reaches maximum in ... 
lasts from 

Effect on tension 



Remarks 



Atropine. 



Atropine sulphate A to 2 
per cent. Most com- 
monly 1 per cent. 



Almost maximum mydria- 
sis ; light reaction lost ; 
increased by cocaine. 



Complete cycloplegia ; be- 
gins later than mydriasis. 

10 to 15 minutes. 
15 to 20 minutes. 
6 to 10 days. 

Doubtful in normal eyes; 
increases tension in eyes 
predisposed to glaucoma. 

Atropine possesses some 
disadvantages, viz. : 

(a) Absorption through la- 
crimal passages, caus- 
ing poisonous symptoms 
(dryness and redness of 
throat and face, faintness, 
staggering, delirium). 

(b) Atropine infiltration, 
redness and swelling of 
eyelids and cheek. 

(c) Follicular conjunctivitis 
from frequent applica- 
tion. 

On account of its sProng and 
lasting action it is the best 
mydriatic for protracted 
use, as in iritis. 



Scopolamine. 



Scopolamine hydrobromate 
^■g to \ per cent. (Accord- 
ing to some it is identical 
with hyoscine.) 



Same as atropine. 



Same as atropine. 

7 to 10 minutes. 
25 minutes. 
4 to 7 days. 

Doubtful ; tension not in- 
creased according to 
Raehlmann. 

Scopolamine is five times as 
powerful as atropine, but 
its effect is of shorter 
duration. In ^ per cent, 
solution it is not more 
poisonous than atropine, 
and less so than duboi- 
sine. It is better borne 
by the conjunctiva than 
atropine. It should be 
used, therefore — 

(a) Where atropine is not 
strong enough to break 
down posterior synechia;. 

(b) Where atropine infiltra- 
tion occurs. 



A few drugs not included in this table have been and are still used. Of these- 
and are not to be recommended. Cocaine as a mydriatic is not very useful when 
Holocaine acts in the same way, without, however, affecting the cornea or cirou- 



1 Those tables buvo been drawn up chiefly by the aid of n paper by Dr. H. SchulU, 

Archiv fur Atigtn 

420 



e various mydriatics, myotics, and local anaesthetics. 



(Pi pil Dilators). 



HOMATROl'l.NE. 



loin atropine hydro 
bro mate 1 per cent. 



ood mydriasis, but 
less than atropine. 



larked, but not com- 
plete cycloplegia. 

2 to 15 minutes. 
D minutes. 
2 to 24 hours. 

lot so liable to raise 
tension as atropine. 



[omatropine is less 
powerful and less 
poisonous than atro- 
pine. On account of 
ita action on accom- 
modation, and the 
short duration of its 
effect, it is the best 
mydriatic far esti- 
mating error* of re- 
fraction. Its effect 
■ increased by the 
addition of cocaine. 



Ephedrine. 



10 per cent. 



Good mydriasis ; 
light reaction 
retained. 



Little or no effect. 



8Jr minutes. 

30 to 60 minutes. 

5 to 20 hours. 

Little or none. 



It does not act 
quickly enough 
for use in prac- 
tice as an aid 
to ophthalmo- 
scopic diagnosis, 
and is more use- 
ful when com- 
bined with ho- 
matropine. 



Myduine. 



A mixture of homa- 
tropine and ephe- 
drine : 
Homatropine O'Ol 
Ephedrine . 1 
Water . . 10 

Mydriasis greater 
than either con- 
stituent ; light re- 
action feeble. 



None. 



8h minutes. 

30 to 40 minutes. 

4 to G hours. 



The mydriasis being 
greater and of 
shorter duration 
than with either 
constituent, and 
having no action 
on the accommo- 
dation, it is well 
suited for ophthal- 
moscopic d iagnosis. 



Edphthalmine. 



Euphthalmine hydrochlo- 
rate 5 per cent. 



Maximum mydriasis; 
light reaction lost. 



Less than homatropine. 



10 to 15 minutes. 
60 to 80 minutes. 
5 to 7 hours. 

None. 



Although a little slower 
than homatropine, it is 
as good a mydriatic, 
but has the advantage 
of acting on the accom- 
modation in only a 
slight degree, and its 
effects pass off much 
more quickly. It is 
also more powerful than 
mydrine, and therefore 
the best mydriatic far 
ophthalmoscopic dia- 
gnosis. It possesses 
no irritating or toxic 
effects, and does not 
injure the corneal epi- 
thelium. 



tunne is the same as atropine. Hyoscyanine and duboisine are very active poisons, 
ployed alone, I, ut it facilitates absorption, and increases the effect of other mydriatics. 
i f m, like cocaine. 



1* B<lf re ? ' r . ,enern M y ,Iriat " ca . Miotica unci AniiHtheticn in dor Augenheilkiinde," 

421 




IL'-J 



CHAPTER XIII. 



GLAUCOMA. 1 

The chief and essential symptom of this disease is Increased 
[ntraocujar Tension — increased hardness of the eyeball — due 
to over-fulness of the globe. 

There is Primary Glaucoma and Secondary Glaucoma. 

In primary glaucoma, the increased tension comes on with- 
out any previous recognisable disease of the eye ; and it is 
with it we have mainly to do in this chapter. 

In secondary glaucoma, the increased tension comes on in 
consequence of obvious antecedent disease in the eye. 

Primary Glaucoma. 

Primary glaucoma is almost invariably a binocular disease ; 
although it does not always attack each eye simultaneously, 
indeed it is more common for the disease to appear in the 
eyes with an interval of months, or longer. 

Of primary glaucoma there are two great kinds — 
Chronic Simple Glaucoma ; and Congestive, or more or less 
Acute Glaucoma. There is also Chronic Congestive 
Glaucoma. 

Increased intraocular tension, as stated, is the chief and 
essential symptom of glaucoma, whatever form of it may 

1 From yXauKos, sea-green. The name was given to the disease by the 
old writers, on account of the greenish reflection obtained from the 
pupil in some cases. But this greenish reflection is seen in other 
diseased conditions, and therefore is not characteristic of glaucoma. 

424 



CHAP. XIII.] 



OLA U COMA. 



425 



come before us; although this increased tension may not 
always be present in the same degree, or at every time. 

If the tips of the index fingers be placed close together on 
a normal eyeball (Fig. 161), and gentle 
pressure made with them alternately, 
it will be observed that the eyeball 
pits slightly on this pressure, and 
that a sensation of fluctuation is given 
to the fingers. The amount of this 
fluctuation varies according to the 
degree to which the eyeball is filled 
with its humours, and also, to some 
extent, according to the thickness of 
the sclerotic coat. The glaucomatous 
eyeball is more resistant — is harder— than the normal globe. 

But there are normal eyes which have a tension below 
the average normal tension, and others which have a tension 
somewhat above the average normal tension ; and, in eyes of 
the latter class, it is occasionally difficult to decide whether 
or not the tension be abnormally high. If it be a question 
of one eye only, then a comparison of its tension with that 
of its fellow decides the question, for the physiological 
tension is always the same in each eye. 

While marked variations from the normal are easily 
observed, some clinical experience is necessary in order to 
appreciate by palpation those degrees of tension which 
are just above or just below the normal; and no other 
method is equally satisfactory. Tonometers have indeed 
been invented and employed, but for clinical purposes the 
educated fingers, used as above described, are to be 
preferred. 

For the purposes of clinical notation certain signs have 
been adopted. Normal tension is indicated by the letter T, 
slight increase of tension by T -4- 1, still higher tension by 
T -f 2, while T 3 indicates stony hardness of the 




420 



DISEASES OF THE EYE. 



[CHAP. xm. 



eyeball. In tbe same way diminished tension is T - 1, 
T — 2, and T 3. T + 1 and T - ? indicate that it is 
doubtful whether the tension be slightly above or below the 
normal. 

The other symptoms of glaucoma are largely due to tbe 
increased tension ; but in chronic glaucoma there are by no 
means so many symptoms as in acute glaucoma. Let us now 
discuss these two great forms of primary glaucoma separately. 




Fig. 1G2. — (Ed. Jaeger), sc, Sclerotic ; ch, Chorioid ; r, Eetina ; of, 
Optic nerve ; ca, Intcrvaginal space ; v', External sheath of the optic 
nerve; E, Excavation of the papilla; M, Margin of the excavation; lc, 
Lamina cribrosa. 

And first as to Chronic Simple Glaucoma, (also known as 

Simple Glaucoma, and as Chronic Non-Congestive Glaucoma). 

Symptoms.- — The tension is raised. Sometimes the eye 
is very hard (T -f- 2, or more), and again it may be but 
slightly raised (T + 1). Even in one and tbe same eye the 
tension usually varies, and may be at one time too high, 
and at another almost, or quite, normal. 

The external appearance of the eye is usually normal, and 
the pupil reacts well to light. The anterior chamber is 
sometimes a little too shallow. 

On examination with the ophthalmoscope, the optic 
papilla is found to be cupped. The optic disc, being the 
weakest part of the ocular wall, is the first place to give 



CHAP. XIII.] 



GLAUCOMA. 



4-27 



way to high intraocular tension ; and after a time it be- 
comes depressed or cupped, the lamina cribrosa being pushed 
back (E, Fig. 162), the cup being sometimes deeper than the 
outer surface of the sclerotic. This cupping of the papilla 
is a most important sign of glaucoma, and differs essentially 
in appearance from the physiological cupping (vide p. 122), 
inasmuch as it occupies the entire area of the papilla, and 
has steep, not shelving, sides. As shown in Fig. 162, the 




Fig. 103.— {Ed. Jaeger), a, Arteries ; v, Veins ; M, Margin of disc ; 
K, Bending of vessels at margin of the disc ; Vp, Vessels on the floor 
of the excavation ; z, Glaucomatous ring. 

walls of the excavation are often hollowed out, and the 
ophthalmoscopic effect of this is to give to the retinal vessels 
the appearance of being broken off at the margin of the 
papilla (Fig. 163), where they pass round the overhanging 
edge of the excavation, and become hidden by it, while on 
the floor of the excavation they reappear. 

The presence of an excavation may be recognised ophthal- 
moscopic^! ly, in the examination by the indirect method, by 



428 DISEASES OF THE EYE. [chap. xin. 



means of lateral motions of the convex lens. It will be then 
seen that, while the whole fundus seems to move along with 
the motion of the lens, the floor of the excavation apparently 
moves in the same direction, but at a slower rate. This 
parallax is the more marked the deeper the excavation. 
The phenomenon is explained by the accompanying figure 
(Fig. 164). If o be the optical centre of the lens being used 
in the examination, and b and a two points lying one behind 
the other, the inverted images of these points will be situated 
at b' and a. The line a b' lies in the visual line of the 




Fiu. 101. 



observer ; and if the lens be moved upward a very little, so 
that the optical centre comes to o, the inverted images of b 
and a will be removed to b 2 and a 2 . If the observer have not 
altered his point of view, it will seem to him that the point b 
has made a more extensive motion than the point a ; or that 
it has moved more rapidly than a, and has glided between a 
and the observer. Short and rapid motions of the lens from 
side to side, or from above downwards, will best show the 
parallax. 

In the upright image, the existence of an excavation may 
be ascertained, by observing that a lens of a different power is 
required in order to obtain a clear image of the margin of the 



CHAP. XIII.] 



OLA ('COMA . 



429 



papilla and of its floor. The depth of the excavation may be 
estimated by noting the difference between these two lenses — 
. /.. if the general fundus of the patient be emmetropic, and 
the emmetropic observer require — 3 D to see the floor of the 
excavation, the depth of the latter is about 1 mm., and in 
the same proportion up to 10 D. 

Besides being cupped, the optic papilla in glaucoma 
becomes atrophied from the pressure, and its consequent 
pallor serves to aid the diagnosis between this and a phy- 
siological excavation. 

Spontaneous pulsation of the arteries on the optic papilla 
may be often noted in glaucoma, or can be produced by 
slight pressure with the finger ; because blood can only be 
forced into these vessels by a pressure greater than that 
opposed to it. In the eye with normal tension there is no 
arterial pulsation, — and slight pressure with the tip of the 
finger would not bring it on, — for the tension of the coats 
of the vessels is greater than the intraocular tension ; and 
therefore the blood passes on in a continuous stream. But, 
in the decidedly glaucomatous eye, the intraocular tension 
opposes so great an obstacle to the arterial flow, that at 
the systole alone can it make its way through. 

Arterial pulsation also occurs, although rarely, in exoph- 
thalmic goitre (see chap, xix.); and it occurs where the 
pressure in the arteries themselves is low (weak heart's 
action, aortic regurgitation, etc.), although that in the 
vitreous chamber be normal. 

Around the margin of tbe glaucomatous excavation, 
especially in chronic glaucoma, one usually sees the whitish 
appearance, termed the glaucomatous ring (Fig. 163), which 
is held to be due to atrophy of the chorioid from pressure. 

Increasing dimness of sight is the only symptom of 
which the patient complains in chronic simple glaucoma. 

An examination of the field of vision will show it to be 
contracted, in consequence of interruption to conduction in 



430 



DISEASES OF THE EYE. 



[CHAP. XIII. 



the retinal nerve-fibres from pressure on tbem at the margin 
of the depressed optic papilla. This contraction of the field 
must always be carefully looked for with the perimeter 
in eight or ten meridians, as it is most important for 
diagnosis and prognosis. The contraction commences at 
the nasal side as a rule, while at the same time central vision 
is lowered, and later on the temporal portion of the field 
becomes contracted, and gradually complete blindness is 
brought about. 

In addition to the perimetric examination of the field, 
Bjerrum recommends that it should be investigated further 
by aid of a black velvet screen two metres square, and a 
small test object. By this means the state of relative 
vision within the field is examined. In glaucoma he finds 
the area of relative defect in the field can always be traced 
to the blind spot, if a sufficiently small test-object be used ; 
or, in other words, that the area of most acute vision, 
and that of relative defect, meet at the blind spot. 

Cases are met with in which the optic disc is cupped 
and pale, and in which increased tension is either not 
present at the time of the examination, or is so slight as to 
be doubtful. And here the diagnosis between glaucoma, and 
primary atrophy of the optic nerve with cupping of the 
disc, may be exceedingly difficult. The examination of the 
field of vision by the ordinary method does not always assist, 
for in each of these diseases it is liable to be contracted ; 
but if the contraction occur with re-entering angles, it 
points to primary atrophy, for this form of field is not found 
with glaucoma. Bjerrum's symptom (vide supra) can come 
to aid here. The effect of a myotic on the intraocular 
pressure may aid the diagnosis, for it would not materially 
influence normal tension, while it would reduce abnormally 
high tension. 

The colour sense usually remains normal in glaucoma 
until a late stage, while in primary optic atrophy it is 



CHAP. XII1.1 



GLAUCOMA. 



431 



defective at an early stage. Again, if slight pressure with 
the tip of the surgeon's finger produce arterial pulsation at 
the optic papilla, it is suggestive of glaucoma, for in a normal 
eye considerable pressure is needed to produce this effect. 

The progress of chronic simple glaucoma is extremely slow 
and insidious, extending often over several years, and ending 
in total blindness, if untreated. It usually attacks both eyes, 
but generally one of them long before its fellow. Sometimes 
chronic simple glaucoma, after a time, takes on the acute 
or the sub-acute form. 

Acute Glaucoma. (Also called Acute Congestive Glau- 
coma.) — In this form, the increase of tension is always very 
marked. In addition there are the following symptoms : — 

Diminished Depth of the Anterior Chamber, from pushing 
forwards of the lens and iris. 

Diminution of the Refracting Power of the Eye, by reason 
of the nearer approach of the latter to a globular shape. 

Diminution of the Amplitude of Accommodation, and 
Anaesthesia of the Cornea, owing to pressure on the ciliary 
nerves as they pass along the inner surface of the sclerotic. 

Opacity of the Cornea, giving its surface a peculiar 
steamy or breathed-on appearance, due to oedema of the 
corneal tissue and epithelium, by infiltration into them 
of the intraocular fluids from high tension. A similar 
appearance, although brought about in a different manner, is 
sometimes seen in iritis and iridochorioiditis, and in 
interstitial keratitis. 

Indistinctness of the Pattern of the Iris, similarly due to 
oedema. 

Opacity of the Aqueous and Vitreous Humours. 

Dilatation and Immobility of the Pupil, the result, accord- 
ing to some, of paralysis of the ciliary nerves, but, according 
to others, of antemia of the iris from pressure on its vessels. 
'Die pupil is oval, with its long axis vertical. 

The Episcleral Veins are large and tortuous, owing to the 



432 



DISEASES OF THE EYE. [chap. xiii. 



pressure on the vasae vorticosse preventing the discharge by 
those channels of the chorioidal venous blood, which must 
then pass off by the anterior ciliary veins. 

Subjective Appearances of Light and Colour, and coloured 
halos or rainbows around lamps and candles (iridescent 
vision), are complained of. 

Pain is a very marked symptom of acute glaucoma, both 
in the eye, and radiating over the corresponding side of the 
head, and is often very violent. 

Vision is greatly affected, and the field of vision, when 
it can be examined, will be found contracted, in cases of 
some standing. 

The Optic Papilla, when the media are sufficiently clear 
to admit of its being examined, is seen to be cupped, if the 
disease have continued sufficiently long to bring about this 
change. 

In acute glaucoma we recognise certain Premonitory Symp- 
toms — viz., sudden diminution of the amplitude of accom- 
modation, evidenced by the rapid onset or increase of 
presbyopia, and the consequent necessity for higher + glasses 
for near work ; and the occasional appearance of coloured 
halos around the flames of lamps or candles, with attacks of 
fogginess of the general vision. The duration of one of these 
foggy attacks may be from a few minutes to several hours. 
Such attacks are apt to occur after a sleepless night, or 
after a meal, and are sometimes accompanied by peri-orbital 
pains. Slight opacity of the aqueous humour, and sluggish- 
ness of the pupil, with some dilatation, are present during 
an attack ; but the eye afterwards returns to its normal 
condition, and remains so for weeks or months, until another 
similar attack comes on. Such a premonitory stage may 
last a year or longer, but cases also occur in which there is 
no premonitory stage. 

The most favourable time for operative interference is 
during this premonitory stage. The operation can then be 



CHAP. XIII.] 



GLAUCOMA. 



433 



performed with technical accuracy in an eye free from con- 
gestion, and with a normally deep anterior chamber. There 
is. too, as yet no loss of sight, nor any degeneration of the 
tissues of the eyeball. The difficulty is to induce patients to 
consent to operation at this period. 

The onset of the True Glaucomatous Attack is usually at 
night. It is accompanied by violent pain radiating through 
the head from the eye, and by pericorneal injection, chemosis, 
and lacrimation. The aqueous humour becomes cloudy, the 
anterior chamber shallow, the iris discoloured, and the pupil 
dilated to medium size and of oval shape, while the cornea 
becomes steamy and anaesthetic. The patient frequently 
complains of subjective sensations of light, and vision is very 
defective, or may be quite wanting. Vomiting very 
frequently accompanies acute glaucoma, and has often led 
to errors of diagnosis, the patient's ailment having been 
taken to be a gastric disease, while the ocular symptoms 
were regarded as mere coincidences, such as a cold in the 
eye, neuralgia, etc. 

An attack such as that just described may, to a great ex- 
tent, pass away in the course of a few days, but a complete 
remission of all the symptoms does not again take place. 
Some defect of central vision is left, or, it may be, some slight 
peripheral defect in the field of vision ; the tension does not 
become quite normal again, and the pupillary motions remain 
slightly sluggish. Another acute attack of glaucoma comes 
on in the course of some weeks or months, and it, too, may 
pass away, leaving the eye in a still worse condition than it 
found it. The attacks gradually become more frequent; and if 
in the intervals the eye be examined, the cornea and vitreous 
liurriour will be found more or less opaque, the optic papilla 
cupped, and pulsation of the central artery of the retina 
may be discovered. Finally, there is no remission from 
the attack, the violent glaucomatous symptoms become 
permanent, and all vision is for ever destroyed. 

28 



43d 



BIS EASES OF THE EYE. 



[CHAP. XIII 



Even when vision has been destroyed, the high tension con- 
tinues, .and gradually produces that disorganisation of the 
tissues of the eyeball known as glaucomatous degeneration. 
The iris becomes atrophied, the lens becomes opaque, and the 
cornea frequently ulcerates, while haemorrhages are apt to 
occur in the anterior chamber. In time the excessive intra- 
ocular tension causes staphylomatous bulging of the sclerotic 
in the ciliary region, or further back ; and, finally, such eyes 
may become the subjects of acute purulent chorioiditis, and 
end in phthisis bulbi. 

Acute glaucoma almost always comes on in both eyes, either 
at the same time, or with an interval, it may be of weeks, or 
of months. 

The , reason for the marked difference between the 
symptoms and course of chronic and of acute glaucoma 
is, probably, that in the former the increase of tension is 
very gradual, and therefore the eye gradually becomes 
accustomed to it ; while in acute glaucoma the increase is 
rapid or sudden, and the circulation of the eye has not time 
to accommodate itself to the new state of things. 

Glaucoma Fulminans is the term given to a form of the 
disease, which is more acute than the ordinary acute 
glaucoma just described. It has no premonitory stage, 
and, coming on with all the symptoms of acute glaucoma 
greatly intensified, does not remit, and causes complete 
permanent destruction of vision in the course of a few hours. 
It is a very rare form. 

Subacute Glaucoma. — This form differs from acute glau- 
coma, in that its premonitory stage merges gradually into 
the actual disease, without the occurrence of an acute attack. 
The eye gradually becomes hard, the pupil dilated, the 
anterior chamber shallow, the aqueous humour opaque ; while 
the cornea is "steamy" and anaesthetic, and the episcleral 
veins are distended. With the ophthalmoscope the cupped 
disc and pulsating arteries may be seen, when the opacities 



chap, xiii.] GLAUCOMA. 435 



of the media permit. Vision sinks, and the field is contracted 
towards its nasal side. The progress of the disease is very 
slow ; and in its course attacks of ciliary neuralgia, with 




Fig. 165. — Diagrammatic representation of normal condition. I. Angle 
of anterior chamber, and ligamentum pectinatum. s. Canal of Schlemm. 
p. Venous plexus of Leber. 

greater increase of the tension, greater opacity of the aqueous 
humour, increase of the corneal opacity and anaesthesia, and 
increased dimness of vision, are experienced. These attacks 




1 U'f. 166. — Diagrammatic representation of glaucomatous condition. 
I'. Obliterated angle of anterior chamber. 

pass ofF in the course of a few days or hours, leaving the 
eye harder and blinder than before. The subacute 
glaucoma sometimes takes on the acute form. It is liable 



DISEASES OF THE WTK 



to bring about the same glaucomatous degeneration of the 
eye as does the latter. 

Elioloyy of Glaucoma. — Glaucoma is a disease of advanced 
life, occurring most usually after fifty years of age, and rarely 
under the thirtieth year. 

Anxiety, sorrow, and influences in general which depress 
the spirits have often been noticed to precede the onset of 
acute glaucoma, but no other immediate causes have been 
recognised. 

Pathology of Glaucoma. — The theory of the disease which 
obtains the most acceptation is the retention theory. It 
has been ascertained that, in glaucomatous eyes, the 
periphery of the iris lies in contact with the periphery 
of the cornea (Figs. 165 and 166), and, consequently, 
obliterates the spaces of Fontana in the angle of the 
anterior chamber, to which point, the effete intraocular 
fluids normally flow through the pupil from the posterior 
part of the aqueous humour. The intraocular fluids in the 
normal eye largely make their exit from the eye into the 
sinus venosus, or canal of Schlemm. The spaces of Fontana 
and the canal of Schlemm are separated from each other 
by delicate walls consisting of a layer of endothelium 
merely, and hence the most favourable anatomical conditions 
for filtration are provided. Moreover, the intimate union 
of the distal aspect of the blood-vessel with the tissue of 
the sclerotic keeps it constantly patent, and in this way 
the, constant outflow of the fluids is assured. Physiological 
experiment, too, has shown, that the intraocular fluids 
escape by this path. The aqueous humour, and other 
fluids, escape also through the veins on the anterior surface 
of the iris, and through the veins of the ciliary body, into 
the venas-vorticosas ; but it is almost certain that the main 
exit is through the canal of Schlemm:. Priestley Smith 
holds that the chief predisposing cause of primary glaucoma 
is an insufficient space — the circumlental space — betwee n 



CHAP. XIII.] 



GLAUCOMA. 



437 



the margin of the lens and the structures which surround 
it, and he attributes the greater liability of elderly- 
people to glaucoma, to the progressive increase in the size 
of the lens, which he has shown to occur as life advances. 
In eyes in which the circumlental space is insufficient, by 
reason either of the original structure of the eye — and small 
eyeballs are specially liable to primary glaucoma, a fact 
often demonstrated by the small size of the cornea in 
the eyes attacked — or of the enlargement of the lens, 
any condition which tends to overfill the veins of the 
head and uveal tract may initiate an attack of acute 
glaucoma, as follows : — -An increase in the amount of blood in 
the uveal tract must be compensated by the expulsion of some 
other fluid from the eye ; consequently, the aqueous humour 
filters out more rapidly than is normal at the angle of the 
anterior chamber. As the contents of the chamber diminish , 
the lens and iris move forwards towards the cornea. Now, 
in the normal eye, and especially in the youthful eye, this 
compensation is effected without danger to the angle of the 
anterior chamber, because the lens is comparatively small, 
the circumlental space large, and the anterior chamber deep. 
But, when the lens and ciliary processes are already in close 
relation to each other, and the anterior chamber is already 
shallow, then any increased fulness of the uveal tract involves 
danger to the angle of the chamber. The turgid ciliary 
processes find insufficient space for their expansion ; they are 
carried forwards together with the lens, and, pressing upon 
the base of the iris, lock up the angle of the anterior chamber. 
Thereupon, the further escape of fluid being impossible, high 
tension of the eyeball is established. According to this 
explanation, then, the high tension is due to impeded escape 
of the intraocular fluid (the retention theoi-y), and depends, 
primarily, upon an increase in the amount of blood in 
I be eye. Priestley Smith considers that, in chronic simple 
glaucoma, the predisposing causes are the same as in acute 



438 



DISEASES OF THE EYE. 



[CHAP. XIII. 



glaucoma ; but that in the former, the vascular disturbance 
being gradual and slight, the vessels adapt themselves to 
the slowly increasing pressure, and the angle of the anterior 
chamber is more or less compressed, but not tightly closed. 

Treatment. — The performance of an iridectomy is the means 
discovered by von Gra?fe, in the year 1857, for the cure 
of glaucoma, a disease which had hitherto been incurable. 
This measure held for many years an undisputed position 
as the remedy for the disease, and has not suffered much 
from the competition of the operation of sclerotomy. 

To ensure the success of an iridectomy for glaucoma, so 
far as possible, it is necessary (1) that the incision should 
be peripheral — i.e., as far back in the corneo-sclerotic margin 
as is compatible with the introduction of the knife into the 
anterior chamber, and with the avoidance of injury to the 
ciliary body ; (2) that the portion of iris removed should be 
wide — i.e., involving about one-fifth of the circumference 
of the iris (see Fig. 158) ; and (3) that it should be abscised 
as close to the root of the iris as possible. 

It is, moreover, important to withdraw the knife very 
slowly from the anterior chamber, when the comeo-scleral 
section is complete, in order that the aqueous humour may 
flow off gradually, lest an intraocular haemorrhage from 
the sudden reduction of tension should occur. The portion 
of iris should be most carefully abscised, so that no tag 
of it may remain in the wound, and become caught in the 
cicatrix in the course of healing. Such an occurrence is apt 
to produce a cystoid cicatrix, which may at a later period 
become the starting-point of irritation, and even of serious in- 
flammation. Some operators prefer von Gra?fe's cataract knife 
for the performance of the operation, but the ordinary lance- 
shaped iridectomy knife is the instrument usually employed. 
For the purpose of reducing the intraocular tension, it matters 
nothing what region of the iris be abscised; but, as a rule, 
the upper quadrant is to be preferred, for there the resulting 



CHAP. XIII.] 



GLAUCOMA. 



439 



coloboma, being covered to a great extent by the upper lid, 
will give rise to less diffusion of light than in any other 
position. 

Immediately after the operation, palpation of the eyeball 
should show a marked diminution of tension. When this is 
not so the prognosis is unfavourable. Should an increase of 
tension occur on the day after the operation, it is of no conse- 
cpience, as it passes off again in the course of the next few 
days. Until then, the anterior chamber will not be re- 
stored, and we see cases where the anterior chamber does not 
appear for a week or more. The bandage should be worn 
until the anterior chamber is completely restored. It is 
desirable to perform the operation with general anaesthesia, 
to secure technical accuracy. The pain for some time after 
the operation is considerable, and should be relieved by a 
hypodermic injection of morphia in the corresponding 
temple. 

Very occasionally, immediately after iridectomy, although 
the operation may have been faultlessly performed, the case 
takes what is termed a malignant course. In these cases 
the lens seems to be violently pushed forwards, blocking the 
wound, obliterating the angle of the anterior chamber, and 
preventing any fluid from escaping from the eye, so that 
soon it is as hard, or harder, than before. This complica- 
tion seems to be caused by the retention of fluid behind the 
lens, and is more likely to occur in cases of chronic simple 
glaucoma, than in the acute forms of the disease. 

The only prospect of saving eyes which take on this 
malignant course is by means of the operation of Posterior 
Sclerotomy. A broad needle, or a Graefe's knife, is entered 
through the sclerotic, 8 or 10 mm. behind the outer margin 
of the cornea, and the blade is given a quarter turn on its 
axis, so as to make the wound gape, or the latter may 
even be somewhat enlarged in a meridianal direction. At 
the same time gentle pressure is applied, by means of 



410 



DISEASES OF THE EYE. [chap. xin. 



the upper lid, on the centre of the cornea. This causes 
fluid to escape through the scleral wound by the side 
of the knife, and it also causes the lens to go back into 
its place, with restoration of the anterior chamber. The 
pressure on the cornea may be maintained with advantage 
for a minute or somewhat longer. This proceeding has 
also been suggested as a cure for glaucoma, but has not yet 
been put into practice. It is probable that it would only 
temporarily reduce the intraocular tension. Posterior 
sclerotomy is sometimes performed to facilitate the operation 
of iridectomy, in those cases of acute glaucoma where there 
is no anterior chamber. 

As a rule, the more acute the form of glaucoma, and the 
earlier in the disease the iridectomy be performed, the more 
favourable is the prognosis in respect of the result which may 
be expected. The saving of normal vision can only be looked 
for in those cases, where it has as yet fallen but little, or not 
at all, below the normal, and where the contraction of the 
field has barely commenced. When the disease has interfered 
seriously with vision (of course we do not refer here to the 
enormous loss of sight immediately attendant upon an attack 
of acute glaucoma, for this is usually restored,) more than 
retention of the status in quo cannot be looked for. And 
even in this respect our prognosis must be most guarded, 
especially in chronic simple glaucoma, when the disease has 
advanced so far, that the contraction of the field is found to 
have approached close to the fixation-point, although central 
vision may still be fairly good. Because in such cases, while 
the iridectomy may prove successful in so far as reduction 
of tension is concerned, yet the contraction of the field — i.e., 
the progress of the atrophy of the optic nerve — is often not 
arrested, and shortly afterwards may be found to engulf the 
centre of vision. Indeed, where the contraction is near 
the fixation-point at one side, and is advanced in other 
directions, it is better not to operate. 



CHAP. XIII.] 



GLA UCOM 1. 



4 11 



In general, while the results obtained from iridectomy 
in acute and subacute glaucoma, on the bases above laid 
down, can be regarded as satisfactory ; in chronic simple 
glaucoma, iridectomy does not act with the same degree 
of certainty. Indeed, it is only in a small proportion of 
the cases of simple glaucoma that sight is saved by iridec- 
tomy. In some cases, although for some time after the 
operation the tension is normal, yet later on it again 
becomes high, and vision continues to fall, and the field 
becomes more contracted. 

Some falling away in vision must be expected in almost 
all cases of chronic simple glaucoma for a time after the 
iridectomy ; but in the favourable cases this is only 
temporary, and the sight gradually returns to its previous 
state, in the course of some weeks. 

Although then, the prospects of retention of sight by 
means of an iridectomy are far from good, yet, as holding 
out the only prospect of retention of any vision, it 
should be recommended to the patient — except in very 
advanced cases- — -at as early a period in the disease as 
possible, before the field has become much contracted. 

When, as is often the case, the patient comes with 
one eye far advanced in the disease, and the other in 
an early stage, it is a question which eye should be 
first operated on. Probably most surgeons operate on the 
worst eye first, with the result that the measure having 
been applied too late, the result is unsatisfactory, and the 
patient declines to allow the better eye, which might be 
saved, to be operated on. 

In such cases the iridectomy should be made on the 
better eye first. 

In cases of acute or subacute glaucoma it has frequently 
been observed that shortly, even within a few hours, after 
the perforin ;i nee of the iridectomy, the other eye, previously 
healthy, or, at most, affected with but slight premonitory 



442 



DISEASES OF THE EYE. 



[chap. xiii. 



symptoms, is attacked with glaucoma. It is probable that 
this is clue to dilatation of the pupil, with pressing of the 
iris into the angle of the anterior chamber, in consequence of 
confinement in the dark room, and eserine should be put into 
the sound eye as a precaution. 

It may here again (vide p. 359) be stated that the use 
of atropine, or of any other mydriatic, in an eye with a 
tendency to glaucoma is liable to bring on an acute attack 
of the disease, and must be carefully avoided in such 
cases. 

If the tension be not relieved by the iridectomy, a 
supplemental iridectomy miy be parformed after a time, 
at the opposite side of the pupil from the first coloboma. 

The Mode of Action of the Operation is not clearly known. 
The view is held that the cure depends, not on the removal of 
the portion of iris, but on the incision in the corneo-sclerotic 
margin, or, rather, on the nature of the cicatrix (filtration 
cicatrix) resulting from that incision. It is believed that 
this cicatrix is formed of tissue, which admits of a certain 
amount of filtration through it of the intraocular fluids, and 
that in this way the intraocular tension is kept down to the 
normal standard. 

Priestley Smith has satisfied himself that, in a large number 
of successful iridectomies, the success is due to a permanent 
corneo-scleral fistula — -not merely a filtration cicatrix — having 
been formed. The same view is held by Treacher Collins, who 
finds that this permanent gap is maintained by prolapse 
of a fold of iris into the wound. The latter author, indeed, 
discards the filtration-cicatrix theory, for which he considers 
there is no evidence. In those cases where a fistula, 
as described, is not formed by the operation, Treacher 
Collins considers that the obstruction becomes freed, either 
by the iris being torn away at its thinnest part — that 
is, its extreme root — thus lexving a large portion of the 
filtration angle open for drainage ; or, by the escape of the 



CHAP. XIII. j 



GLAUCOMA. 



443 




aqueous and the drag on the iris, incidental to ths iridectomy, 
being sufficient to dislodge the periphery of an iris, which 
has only recently come into apposition 
with the cornea. 

Sclerotomy. — From the point of view 
of the filtration-cicatrix theory, this 
operation was devised as a method for 
relief of glaucoma without iridectomy. 
It is employed mainly in chronic simple 
glaucoma — a form in which, as has been stated, iridectomy 
is less satisfactory than in acute or subacute glaucoma. 
Care must be taken that the pupil is contracted to pinhole 
size, or nearly so, when the operation is about to be per- 
formed, as otherwise the danger of prolapse of the iris is 
very great. In those cases where eserine will not produce a 
sufficient myosis, sclerotomy should not be performed. 
. The instrument used for performing the operation is von 
Graefe's cataract knife. A speculum having been applied, 
and the eyeball fixed, the point of the knife is entered into 
the anterior chamber, through the corneo-sclerotic margin, 
at a point of its circumference corresponding to that selected 
for the puncture in cataract extraction, but 1 mm. removed 
from the corneal margin, as represented at a in Fig. 167. 
The counter-puncture is made at a point (b) corresponding 
to this, at the other side of the anterior chamber. With 
a slow sawing motion of the knife the section is enlarged 
upwards, until only a bridge of tissue, about 3 mm. broad, 
remains (at c), and this is left undivided, the better to 
guard against prolapse of the iris. The knife is now slowly 
withdrawn from the eye, care having been first taken that 
the aqueous humour is thoroughly evacuated, which can be 
effected by tilting the edge of the knife slightly forwards, so 
as to make the lips of the wound gape somewhat. If the 
pupil be quite round at the conclusion of the operation, the 
bandage may be applied, a drop of solution of eserine having 



DISEASES OF THE EYE. 



[chap. xiii. 



been first instilled; but if the pupil be oval, or of other 
irregular shape, a tendency to prolapse of the iris is indicated, 
and the hard rubber or silver spatula should be introduced 
into the anterior chamber, to restore the pupil to its normal 
shape by gentle pushing of the iris. If there be an actual 
prolapse of the iris, an attempt may be made to repose it 
with the spatula ; but should this not prove satisfactory the 
prolapse is to be abscised with scissors, thus turning the 
sclerotomy into an iridectomy. 

Although the operation has not gained many adherents, yet 
there are some who regard it as of great value in the earlier 
stages of chronic glaucoma, before the sight is much reduced. 
In those cases Hichardson Cross employs the following proce- 
dure. The pupil, having been contracted with eserine, a broad 
keratome is passed — as though an iridectomy were about to 
be made — from a puncture about 2 mm. outside the corneal 
margin into the anterior chamber. A wide wound is made, 
and the knife is carefully withdrawn to avoid prolapse of 
iris. Cross recommends this sclerotomy, too, when high 
tension recurs after being temporarily relieved by an iridec- 
tomy. The operation may be repeated again and again 
without danger, should the case demand it. 

* Sympathectomy. — Excision of the superior cervical ganglion 
of the sympathetic nerve is a new method for the treat- 
ment of glaucoma, which is merely mentioned here ; for, 
although of interest, it does not seem likely to come into 
general use. It is said to act by contraction of the pupil, 
and reduction of the intraocular blood pressure. 

The Treatment of Glaucoma by Myotics. — Eserine and pilo- 
carpine as eye-drops in 1 per cent, solutions often have the 
power of reducing glaucomatous tension. This power depends 
on the contraction of the pupil, and consequent drawing 
away of the base of the iris from the angle of the anterior 
chamber ; and, if the myotic does not contract the pupil 
greatly, it will not reduce the tension. Cases of acute 



CHAP. XIII.] 



GLAUCOMA. 



1 1 



glaucoma, brought on by the injudicious use of atropine, 
may frequently be completely and permanently relieved by 
a myotic instilled a few times. In acute glaucoma of the 
ordinary type, the use of a myotic in the premonitory stage 
will often postpone the true glaucomatous attack, and even 
sometimes relieve the latter for the time ; but tbe myotic 
treatment cannot produce a radical cure, and it should only 
be used to preserve the health of the eye, until the operation 
is performed. In chronic simple glaucoma, also, myotics 
bring down the tension if they contract the pujail, and may 
be used in those cases where the patient positively declines 
an operation, or where an operation in the fellow eye has 
not resulted satisfactorily, or where an operation is contra- 
indicated by a very contracted field. The anti-glaucomatous 
action of tbe myotic only lasts so long as the pupil is con- 
tracted, and it must consequently be applied once or twice in 
twenty-four hours. 

In the myotic treatment of glaucoma, Priestley Smith 
recommends the combination of cocaine with the myotic in 
such proportions (say, about \ per cent, of cocaine to 1 per 
cent, of the myotic) that the myotic will have the mastery 
over the pupil. For although, like every dilator of the 
pupil when used alone, cocaine may promote high tension, 
yet it has the powers, invaluable in glaucoma, of contracting 
the ciliary blood-vessels, and of diminishing the sensibility 
of the ciliary nerves ; and, when used in the foregoing 
manner, the advantage of each drug may be obtained, without 
any of the disadvantages of either. 

It may be here once more stated that, while myotics 
possess the power of reducing glaucomatous tension, atropine, 
and all mydriatics, bring on glaucoma, where there is 
already a tendency to it. In all old people, therefore, 
before atropine is used, it is well to ascertain that the 
tension is not too high. 

Treat/merit of Painful Blind Glaucomatous Eyes. — Eyes blind 



DISEASES OF THE EYE [chap. xiii. 



of acute glaucoma may, as has been stated, continue to 
be painful ; and to render the patient's life very miserable. 
Iridectomy is very commonly performed to relieve the pain, 
although all hope of restoration of sight is lost; but the 
operation sometimes fails in its object, and excision, or 
evisceration, must be resorted to. Mules's operation should 
not be performed here. 



Secondary Glaucoma. 

In addition to the different forms of primary glaucoma 
above described, we find, as already stated, that high tension 
occurs as a sequel of diseased conditions previously existing 
in the eye. There are several diseased states which are 
liable to become complicated with glaucomatous tension ; 
but it should be clearly understood that, in almost every 
instance, the immediate cause of the high tension is the 
same as in primary glaucoma — namely, a closure of the angle 
of the anterior chamber. 

The following are the chief conditions which are liable to 
lead to secondary glaucoma : — 

a. Complete Posterior, or E-ing Synechia (vide p. 350). 
The iris, being pushed forwards by the aqueous humour pent 
up in the posterior part of the aqueous chamber, is pressed 
tightly against the cornea, and obliterates the angle of the 
anterior chamber and the ways of exit. An iridectomy 
relieves the high tension here. 

b. Perforating Wounds or Ulcers of the Cornea, followed 
by incarceration of the iris in the resulting cicatrix. The 
iris, being drawn tautly towards the cornea, a large portion, 
or the whole, of the filtration angle may be closed by it. 
An iridectomy is indicated. 

c. Dislocation of the Crystalline Lens into the Anterior 
Chamber. Here the normal flow of the intraocular fluids 
through the pupil, towards the filtration angle, is arrested 



CHAP XIII.] 



GLA UCOMA . 



447 



by reason of the presence of the lens in the anterior 
chamber. The onward current then presses the iris against 
the posterior surface of the lens, and the root of the iris, 
which is unsupported by the lens, against the periphery of the 
cornea, and in this way the angle of the anterior chamber 
is closed. In these cases the lens must be removed from 
the eye. 

d. Lateral (traumatic) Displacement of the Crystalline Lens. 
The lens, being pushed in between the ciliary processes 
and the vitreous humour, drives the root of the iris 
forwards against the cornea at that place, while in other 
parts of the circumference the displaced vitreous acts 
in the same way. In these cases, too, the lens must be 
removed. 

e. Injury of the Crystalline Lens (vide chap. xiv.). The 
swelling lens pushes the iris forwards against the angle of 
the anterior chamber. Evacuation of the lens should be 
performed. 

/. After Cataract Extraction. For explanation of this see 
chap. xiv. 

g. Intraocular Tumours (vide p. 403). The growth of the 
tumour gives rise to a transudation of serum from the 
chorioid which detaches the retina, and after a time pushes 
the lens, the ciliary processes, and the iris forwards, and thus 
closes the nitration angle. 

It. Serous- Cyclitis, or Iritis. Here the filtration angle is 
not closed. Priestley Smith thinks that the increased tension 
is flue to diminished filtration-power of the eye, and perhaps 
by tissue changes around the filtration angle, and by deposit 
of exudation in the angle of the anterior chamber. 

Another, and peculiar, form of secondary glaucoma is 

"Haemorrhagic Glaucoma. — Retinal hemorrhages of the 

ordinary type are sometimes followed, a few weeks later, by 
increased intraocular tension, which generally assumes the 
symptoms of acute or subacute glaucoma, and, more rarely, 



448 DISEASES OF THE EYE [chap. xiii. 



those of chronic simple glaucoma. A satisfactory explanation 
for these cases has not been offered. When such a glaucoma 
becomes pronounced, it is not usually possible to distinguish 
it from a primary form of the disease. This disease is 
practically hopeless. Iridectomy is more likely to do harm 
than good, the operation being almost invariably followed 
by fresh intraocular hamiorrhages, and by a further increase 
of tension. Sclerotomy is said by some to act with fairly 
good results ; but the myotic treatment is powerless. 

•Congenital Hydrofhthalmos. 

Also known as Buphthalmos, and as Cornea Globosa. It is 
a glaucomatous disease of early childhood, of which the in- 
cipient stages are believed to be intra-uterine. The cornea 
becomes enormously enlarged in diameter, the anterior 
chamber deep, the iris trembling, and the sclerotic thinned. 
Increase of tension, often attended by severe pain and 
cupping of the optic papilla, are usually present. 

The Pathology of the disease is obscure. Treacher Collins 
holds that it is a failure in the separation of the iris from 
the back of the cornea at its extreme periphery, in course 
of the development of the eye, whereby the angle of the 
anterior chamber is blocked ; while E. von Hippel believes 
it to be the result of an intra-uterine inflammation. 

Treatment. — Iridectomy and sclerotomy are alike followed 
by disastrous results in this disease. The myotic treatment 
is the only one applicable, and in a few cases it arrests the 
disease. 



CHAPTER XIV. 



DISEASES OF THE CRYSTALLINE LENS. 

Cataract, by which is meant an opacity of the lens, may be 
said to be the only disease of this part of the eye. Cataract 
may be complete — occupying, in its final stage, the whole, 
or nearly the whole, of the lens ; or partial — occupying only 
part of the lens, and with little or no tendency to extend 
to other parts of it. 

Complete Cataracts. 

Of these, the most common is Senile Cataract. It occurs 
in persons of over fifty years of age, rarely in those under 
forty-five years of age. 

Progress, Pathogenesis, and Etiology of Senile Cataract. — In 
incipient senile cataract, the opacity is found in the cortical 
layers of the lens, especially at its equator, and in the 
latter position can often only be detected with transmitted 
light from the ophthalmoscope mirror, or with focal illu- 
mination, even when the pupil is dilated with atropine. 
This opacity takes the form of lines, or of triangular sectors, 
of which the bases are towards the equator of the lens, 
while the apices are towards its centre. These lines and 
sectors look black with transmitted light, but grey with 
focal illumination, and between them clear lens-substance is 
present. Or, incipient cataract may first appear as a diffuse 
opacity in the layers surrounding the nucleus of the lens. 

44:) 29 



450 



DISEASES OF THE EYE. 



[chap. XIV. 



Or, the opacity may commence both near the equator and 
around the nucleus at about the same time. Or, again, the 
opacity may in the beginning be disseminated through the 
cortex, in the form of flocculi, dots, and lines. In some 
cataracts, in a very incipient stage, there are no absolute 
opacities ; but with weak transmitted light — i.e., from a plane 
mirror — numbers of fine dark lines will be seen in the lens, 
which vanish and reappear according as the incidence of the 
light is altered ; while a little later true opacities make 
their appearance. Gradually the cataract extends to other 
parts of the lens, until the whole cortical portion is opaque. 

In senile cataract, the very nucleus itself does not become 
cataractous, although it is usually sclerosed (harder and drier). 
Sclerosis of the nucleus of the lens is a physiological con- 
dition of advanced life, and will be found in many an eye 
where there is no cataract. It gives to the senile non- 
cataractous lens, as seen with a dilated pupil or with focal 
illumination, a peculiar smoky appearance, which is often 
mistaken by inexperienced persons for cataract; but examina- 
tion with transmitted light will show that there is no true 
opacity. When a senile cataract has become complete, the 
sclerosed nucleus imparts to its centre a brownish or yellow- 
ish hue, while the other parts of the lens are of a greyish 
white. As a rule, the most peripheral layers of the cortex 
are the last to become opaque. Accordingly as the lens 
becomes opaque, it often swells somewhat ; and in those cases 
the anterior chamber becomes a little shallower. 

Until the whole cortex is opaque, a clear interval will be 
present between the iris and the cataractous part ; and. on 
examination with the oblique light, a shadow of the iris will 
be thrown on the cataractous part at the side from which 
the light comes; and the cataract, in this way, is proved 
to be immature in the strict sense. If the whole cortical 
substance be opaque, the thickness of (lie capsule alone will 
intervene between the pupillary margin and the opacity, and 



chap, xiv.] THE CRYSTALLISE LESS. 



451 



no shadow of the iris can be thrown on the latter. In 
addition to this examination with focal light, the pupil 
should be dilated, and the lens examined by transmitted 
light from the ophthalmoscope mirror, when a completely 
opaque cataract should permit of no red reflection being 
obtained, in any direction, from the fundus oculi. 

As soon as the whole of the cortical substance has 
become opaque, any swelling of the lens subsides, and the 
anterior chamber finally regains its normal depth. If there 
be no glittering sectors in the cortex, the cataract is now 
"mature," or " ripe " for operation — i.e., if an extraction opera- 
tion be now undertaken, it is possible to deliver the lens 
in its entirety ; whereas, prior to this stage, some cortical 
substance would have been liable to adhere to the capsule, 
and be left behind. 

But a cataract is immature, despite the absence of shadow 
from the iris, and of the illuminable pupil, and even though 
the anterior chamber be of normal depth, if the cortex present 
well-marked, glittering sectors. The glitter of the different 
sectors varies with the angle of illumination, so that the 
surface appears faceted. In such a lens there are thin 
transparent flakes, as well as opaque flakes, close beneath 
the capsule ; and, if extraction be undertaken, the former 
are very apt to remain within the eye in spite of every 
effort to remove them. A few months later the sectors lose 
their sharp contour, break down, and finally disappear. We 
can then depend upon the exit of the whole cataract. 

Yet in persons over sixty years of age, in whom the 
nucleus is usually large, many a cataract can be completely 
removed which does not come \np to the strict standard 
of maturity just laid down ; and, at that time of life, the 
surgeon need not hesitate to operate, without waiting for 
absolute maturity, if the patient be materially incommoded 
for want of sight. 

The foregoing is the most common course of events in the 



452 



DISEASES OF THE EYE, 



[chap. xiv. 



progress of a senile cataract ; but there is a rather rare form 
of it, in which total opacity of the cortical layers never does 
come about. In this form the lens is occupied by radiating 
linear opacities up to the very capsule ; but between these 
opaque lines there are clear intervals, which may even admit 
of the fundus oculi being examined, although dimly, and 
which allow of a certain amount of sight. These cataracts 
can be successfully removed. 

After the stage of maturity a cataract gradually goes on 
to be hypermature. Here one of two changes takes place : 
either the cortical substance breaks down, and becomes fluid, 
the nucleus retaining its consistency, and gravitating to the 
lowest part of the capsule (Morgagnian cataract) ; or, more 
commonly, the cortical substance dries up, as it were, and 
finally comes to form, with the nucleus, a hard flat disc. 
Accompanying these changes in the lens substance are 
changes in the epithelium lining the inner surface of the 
anterior capsule, which result in a thickening of the capsule. 
In a Morgagnian cataract the fluid cortex Anally undergoes 
absorption, and the anterior and posterior capsules come in 
contact (cataracta membranacea). In some cases the capsule 
remains more or less transparent, and the sight may greatly 
improve. Some cases are on record of spontaneous cure 
of cataract, clue to intracapsular absorption. 

The investigations of Priestley Smith have shown that 
a diminished rate of growth of the lens precedes the forma- 
tion of cataract ; and it is held that the cataractous process 
in the senile lens is the result, in the first instance, of a 
rapid sclerosis and shrinking of the nucleus. If the process 
of sclerosis and shrinking be very gradual, cataract does not 
appear, because the cortical layers of the lens have time to 
accommodate themselves to the altered state of things ; but, 
if the shrinkage be rapid, the cortical layers cannot so 
rapidly accommodate themselves, and then the fibrillffi of 
these layers become separated somewhat from each other, 



CHAP. XIV.] 



77/ E ( It ) '8 7 •. 1 L L L\ E L ]<L\ S 



453 



and fluid collects in the interspaces. This fluid it is which 
causes the disintegration of the lens substance, gradually 
leading to opacity of the whole lens. As the opacity 
increases, more fluid is present in the lens, and it is this which 
causes the swelling of the lens already referred to. When 
the whole cortex has become opaque, the fluid contents begin 
to diminish, and the lens returns to its normal size. Senile 
cataract, then, is entirely a local process, and is not depen- 
dent on any disordered state of the general health. 

The dimensions of the nucleus vary a good deal. In some 
cataracts it is very small, and these are called soft cataracts, 
as they consist chiefly of the soft cortical substance. In 
others — and as a ride in patients over sixty years of age — 
the nucleus is large, and these are called hard cataracts, 
although they are not hard throughout. The size of the 
nucleus can be estimated pretty accurately by the extent 
and intensity of the yellowish or brownish reflection, which 
is obtainable by focal illumination from the centre of the 
cataract. 

In some senile cataracts, the sclerosis is not confined to 
the nucleus, but extends to the cortical layers as well. This 
causes much disturbance of sight, and the term cataracta 
nigra is given to these lenses, from their very dark hue, 
although they are not cataracts in the true sense of the 
term. They require operation, and, as they are always of 
large size, wide openings have to be made to deliver them. 

In the lenses of young people there is no nucleus: conse- 
quently, in the complete cataracts of children and of young 
adults, there is no nucleus ; the whole lens becomes opaque, 
and the cataract is always soft. Although the starting- 
point of cataract in children and young adults cannot be a 
shrinking of the nucleus, as there is none, yet the opacity is 
no doubt due to the taking up of fluid by the lens. 

The natives of India are very prone to cataract, and at an 
early time of life, as are also persons whose business exposes 



151 



DISEASES OF THE EYE. 



[chap. xiv. 



their eyes for hours at a time to the heat and glare of 
furnaces — e.g., glass-blowers, smiths, cooks, etc. 

The Symptoms to which senile cataract gives rise consist, 
in the earliest stages, in the appearance of motes before the 
eyes and of monocular polyopia. Motes are complained of 
also in disease of the vitreous humour ; but in those cases 
they float over a large portion of the field of vision, while in 
commencing cataract they occupy always the same relative 
position in the field. The polyopia is the result of irregular 
refraction in the lens, which causes many images of the 
objects looked at to be formed on the retina. This symptom 
seems to annoy the patients more especially in the evening, 
when they look at gas or candle flames, the moon, etc. It 
is often complained of before there is any actual opacity in 
the lens, at a time when only the clefts filled with fluid 
between the fibrillar can first be detected with weak trans- 
mitted light from the ophthalmoscope, as dark lines vanishing 
and reappearing according as the incidence of the light is 
altered. 

In some cases of incipient cataract there is an increase in 
the refracting power of the lens, with the result that the 
patient becomes slightly myopic, if, previously, he have been 
emmetropic. 

Gradually, as the opacity of the lens extends to other 
parts of it, the acuteness of vision becomes affected ; and this 
is the more marked the more the cortex at the anterior and 
posterior poles of the lens is involved. In those cases where 
the equatorial parts of the lens are but little affected, while 
the polar regions are a good deal affected, the patients see 
better in the dusk, or with their backs to the light, than 
when their eyes are exposed to a strong light. The reason 
for this is that in the dusk the pupil is dilated, and light 
can pass through the clearer periphery of the lens, while in 
a strong light the pupil is contracted. On the other hand, 
when the opacity is confined rather to the equator of the 



CHAT. XIV.] 



THE CM YSTALLINE LltiNS, 



455 



lens, a strong light is not disturbing to sight ; or, if the 
centre of the lens be quite clear, a strong light may even be 
agreeable to the patient. 

According as the lens becomes more and more opaque, the 
acuteness of vision is proportionately reduced, until, finally, 
even large objects cannot be discerned, and only quantitative 
perception of light is left. Some cataracts, however, when 
quite ripe, still admit of finger-counting at a few feet. 

In advanced stages of the disease, as the opacities occupy 
a great portion of, or the entire' cortex, they are easily 
recognised even by ordinary daylight, often giving a greyish 
appearance to the pupil. Inflammatory exudation of some 
standing in the area of the pupil would afford a somewhat 
similar appearance, but would be attended by other signs of 
the previous inflammatory process, such as synechias, dis- 
organisation of the iris, etc., and it would be seen to lie 
more in the plane of the iris than does any lental opacity. 

The length of time occupied by the ripening of a cataract 
varies in different cases from a few months to many years. 
In the very old the progress is, in general, more rapid than 
at an earlier time of life. That form which commences at 
the equator as fine lines is slower than that with flocculent 
opacities, or than that in which the cortex around the 
nucleus is likewise implicated at an early period. 

All examinations as to the condition of the lens are 
rendered easier and more conclusive if the pupil be pre- 
viously dilated with atropine ; but the tension of the eye 
should be ascertained before atropine is instilled, lest 
glaucoma, or a tendency to it, be present. 

Treatment. — No external local applications, nor internal 
medicines, are of any avail in the treatment of cataract at 
any stage. Removal of the cataract from the eye by 
operation is the only cure for blindness caused by it. 

In cases of incipient cataract, or in those, rather, which 
have advanced somewhat beyond this stage, we often find 



456 



DISEASES OF THE EYE. 



[chap. xiv. 



that vision is improved, or made more pleasant, by the 
wearing of tinted glasses to moderate the light. With com- 
mencing cataract, where slight myopia has come on, low 
concave glasses for distant vision will be found of service ; 
while, for reading, stenopeic glasses sometimes give good 
results. Yet, as a rule, patients are unwilling to use any 
of these aids. 

Dilatation of the pupil with atropine is in many cases 
of the greatest benefit, especially where the nucleus is much 
more opaque than the cortical portion ; but sometimes the 
diffusion of light resulting is most distressing to the patient, 
and greater impairment and confusion of vision are produced, 
and for this reason care in the prescription of atropine is 
demanded. 

Patients with incipient or advancing cataract may, with 
immunity, be allowed to make every use they can of the 
sight they possess ; and the surgeon should give them hints 
as to the arrangement of light in their rooms, and for their 
work, etc., so as to enable them to employ their sight to the 
best advantage. 

The truly distressing period in the progress of cataract, 
when both eyes are affected, lies between the advent of that 
degree of blindness which incapacitates the patient for reading 
or writing, or for making his way about alone, and the occur- 
rence of maturity, or of that degree of maturity which is 
deemed requisite for successful removal. This is often a 
lengthened time ; it may be months or years. Fortunately, 
in many instances the cataract in one eye is much more 
advanced than that in the other ; and then no such trial 
need be gone through. 

* Artificial Ripening. — For the purpose of hastening the 
maturity of a cataract, when the patient has become in- 
capacitated as above, the following method is sometimes 
used. The anterior chamber is paracentesed, and, when 
the aqueous humour has run away, the lens is massaged 



CHAP. XIV.] 



THE CRYSTALLINE LENS, 



457 



with gentle circular motions, with the angle of a strabis- 
mus hook, or other suitable instrument, applied to the 
anterior surface of the cornea. The circular massage must 
be applied, through the cornea, to the entire surface of the 
lens as far as its very periphery. Within forty-eight hours 
the cortex becomes opaque. The proceeding acts by derang- 
ing the epithelium of the anterior capsule, after which 
the aqueous humour can pass through the intact capsule, 
and produce disorganisation of the lens fibres, as occurs 
after the operation of discission. Care must be taken 
that the pressure be not violent, or the capsule may 
be ruptured, or severe iritis may be caused. This 
measure is employed less frequently, since it has become 
the practice to extract cataract in many cases before 
maturity is reached. 

The question, whether the cataract in one eye should be 
extracted until both eyes are blind, is often asked by patients. 
The answer is : — A patient with one mature cataract, and 
the other progressing towards maturity, should have the ripe 
cataract removed. Hypermaturity is thus avoided, and also 
the stage of blindness above referred to. Again, if there be 
a ripe cataract in one eye, and not even incipient cataract in 
the other, it is often advisable to operate for the purpose of 
increasing the binocular field of vision. 

Complete Cataract of Young- People. — The spon- 
taneous occurrence of total cataract in the youthful lens is 
of rare occurrence, and its pathogenesis is still unknown. 

Treatment. — Discission. 

Diabetic Cataract. -This is a complete opacity of the 
crystalline lens occurring in diabetes, and due to disturbed 
nutrition. It has been proved by experiment that cataract 
can be produced by injecting solutions of sugar into the 
blood ; but analysis of the aqueous humour in diabetic 
patients shows, tliat the amount of sugar contained in it is 
not sufficient to account for the cataract. The cataract does 



45S DISEASES OF THE EYE. [chap. xiv. 



not differ in appearance or consistency from other cataracts, 
according to the time of life of the patient. 

Treatment and Prognosis. — Contrary to a very general 
opinion, these cases are not very unfavourable for extraction 
operations. We have operated on cases of this kind, 
and always with success, save once, when the eye was lost 
by intraocular hsemorrhage ; and we have seen such cases 
operated on successfully by others. There is no other 
method of restoring sight to these patients, who often live 
many years. But occasionally patients operated on for 
diabetic cataract die of coma within a fortnight or so 
after the operation. 

The operation of discission in these cases is apt to be 
followed by severe iritis. 

Complete Congenital Cataract.— Children are some- 
times born with crystalline lenses opaque in all their layers, 
while the other tissues of the eye are healthy. With con- 
genital cataract defects of the chorioid or retina, or congenital 
amblyopia without ophthalmoscopic appearances, are also some- 
times present, and these are usually indicated by nystagmus. 

Treatment. — Discission. 

* Black Cataract. — This name, as above stated, is some- 
times given to cases of extreme sclerosis of the lens, in 
which it assumes a dark brown colour ; but in other cases 
the lens is really black, the pigment being derived from the 
blood (hfemin, or hsematiu). The prognosis for an operation 
in these latter cases is not good, as they are often com- 
plicated with disease of the chorioid, or with hajmorrhages 
in the vitreous humour. 

Partial Cataracts. 

These are nearly all congenital. 

* Central Cataract. — This is a congenital and usually 
non-progressive form. It is an opacity of the central, or 
oldest, lens-iibres, while the peripheral layers remain clear. 



chap, xiv.] THE CRYSTALLINE LENS. 459 



Treatment. — Discission or iridectomy. 

Zonular, or Lamellar, Cataract. — This is congenital, or 

forms in early infancy, and is the most common kind of 
cataract in children. It usually is present in both eyes, but 
it has been seen in one eye only. In it the very centre of the 
lens is clear (Fig. 168, diagrammatic), while around this is a 
cataractous layer or zone, and outside that again the 
peripheral layers are transparent. Most of these cases 
are non-progressive, but occasionally the whole lens 
does become opaque, and usually then there have 
been previously some slight opacities in the otherwise yig. 
clear cortical layers. 168, 

With oblique illumination, the cortical layers of the lens 
are seen to be clear, while towards the centre of the lens a 
uniform grey circular opacity will be observed. The diameter 
of this opacity may be small, perhaps not more than 3 mm. 
or 4 mm., or it may extend very nearly to the equator of the 
lens. If the pupil be dilated, and the lens examined with 
transmitted light, the cataractous portion will be seen as a 
more or less dark disc in the centre of the lens, while all 
around it is seen the red light reflected from the fundus 
oculi. The centre of this disc is either of the same degree 
of darkness as its margin, or but very little darker ; and this 
point serves to distinguish this form of cataract from one in 
which the whole centre of the lens is opaque. In the latter 
case it is evident that the centre of the opacity must be 
darker than its margin. In many cases small radial opacities 
are seen round the equator of the lens, passing from the 
anterior to the pasterior surface, their concavity embracing 
the circumference of the central opacity. They are called 
riders (Fig. 168). 

It is probable that lamellar cataract is due to some transient 
disturbance of nutrition in utero, occurring at the time the 
affected layers of the lens are being laid down. But against 
this view is the fact that one half of the lens only may 




4(>0 



DISEASES 01 THE EYE. 



[chap. xiv. 



present the appearance of zonular cataract. The subjects 
of it are usually rickety, as shown by the irregular and 
imperfect development of the teeth (Fig. 169), and by 

rachitic alterations in the bones 
of the skull. Convulsions during 

o 

infancy in these patients are 
common. 

The Treatment of central lental 
Fig. 1G9. Kachitic Teeth. cataract, and of zonular cataract, 

is similar, and consists in either 
discission or iridectomy. The latter is very decidedly to 
be preferred in those cases in which the central opacity 
is so small that, on dilatation of the pupil, the acuteness 
of vision, with the aid of a stenopeic slit, is increased 
in a satisfactory degree. When the improvement is hut 
slight, the breaking up of the lens with a needle is indi- 
cated. The advantage of iridectomy over discission, when 
the former can be adopted, is that no spectacles are after- 
wards required, and that the power of accommodation is 
retained. 

Congenital cataracts may be needled any time after denti- 
tion is completed. 
Anterior Polar, or Pyramidal, Cataract may be either 

congenital or acquired. In the former case it must be referred 
to some inflammatory disturbance occurring about the third 
period of development 
of the lens. In both 
cases the mode of origin 
of the opacity is the 
same, whether it be 
punctiform, flakelike, 
or pyramidal — namely, by contact of the lens with an 
inflamed cornea. In foetal life this may occur without any 
perforation of the cornea, as there is then no anterior chamber. 
Fig. 170 shows a case, in which in the left eye a filament 





CHAP. XIV.] 



THE CRYSTAL LI XE LEXS. 



4G1 



connects the disc-like anterior polar cataract with an 
opacity of the cornea. In the right eye there is a pyramidal 
cataract. After birth a perforating ulcer of the cornea is a 
necessary precursor of it, but the ulcer need not be central 
(p. 152). This contact with an inflamed and ulcerating cornea 
may lead to subcapsular cell-proliferation, at that portion of 
the capsule which is exposed in the pupillary area, and to 
consequent subcapsular opacity in this small area. 
No Treatment is required, as vision is not affected. 

* Fusiform, or Spindle-Shaped, Cataract is also con- 
genital, and is rare. It consists in an axial opacity extend- 
ing from pole to pole, and may be combined with central or 
lamellar opacity. 

The foregoing forms of cataract, with the exception, 
perhaps, of the anterior polar and genuine black cataract, 
are primary ; that is to say, they are not dependent on, or 
the result of, disease in other parts of the eye. 

Secondary Cataract. 

Some diseased states of the eye give rise to secondary 
cataract. 

Of this a partial kind is 

* Posterior Polar Cataract. — This form is seen, with 

transmitted light, as a star-shaped or rose-shaped opacity in 
the most posterior layers of the posterior cortical substance, 
its centre corresponding with the posterior pole of the eye. 

Posterior polar cataract is usually found in eyes which 
are the subjects of disseminated chorioiditis, retinitis 
pigmentosa, or diseased vitreous humour. It sometimes 
progresses, and becomes a complete cataract; and then 
the prognosis for sight after extraction is not very good, 
owing to the disease which is present in the deep parts of 
the eye. 

The additional disturbance of sight caused by the presence 



462 



DISEASES OF THE EYE. 



[CHAP. XIV. 



of posterior polar cataract depends a good deal upon its 
density. 

Total Secondary Cataract often ensues upon contact of 

the lens with inflammatory products in the eye — e.g., where 
false membranes have been produced by inflammation in the 
uveal tract. It is called Cataracta Acer eta, when the iris 
or ciliary processes are adherent to it. Cataract is also 
caused by detachment of the retina, intraocular tumour, 
absolute glaucoma, dislocation of the lens, etc. The reason 
of this is that the lens, in these cases, imbibes abnormal 
nutrient fluid from the diseased tissues with which it is 
in contact. 

Such cataracts often undergo a further degeneration, and 
become calcareous. Calcareous cataracts are easily recognised 
by their densely white or yellowish-white appearance ; and 
almost always indicate deep-seated disease in the eye, even 
when the functions, so far as they can be tested, are fairly 
good. 

These secondary cataracts rarely come within the rauge of 
Treatment, as the diseases which give rise to them are usually 
destructive of sight. When, occasionally, they can be dealt 
with they should be extracted. 

The term secondary cataract is also used in cases in 
which, after a cataract extraction, the capsule of the crystal- 
line lens, which is left behind, presents an obstacle to good 
sight, although here it is not a very suitable term. This 
will be referred to again, and is not to be classed with the 
conditions dealt with in this paragraph. 

Capsular Cataract. 

By this term is meant an opacity of the anterior capsule, 
or of the capsular epithelium. It is usually confined to 
the centre or anterior pole, and is most frequently seen in 
over-ripe senile cataracts, and in secondary cataracts. 



CHAP. XIV.] 



THE CRYSTALLINE LENS. 



463 



Traumatic Cataract. 

Every injury which opens the capsule of the lens is liable 
to cause cataract, by reason of the admission of some of the 
surrounding fluids to the lenticular substance. 

Perforating injuries with sharp instruments, or the en- 
trance of small foreign bodies — in both cases, as a rule, 
through the cornea — are the most common injuries that 
produce traumatic cataract. But blows upon the eye, without 
any perforating wound, also, although rarely, produce cataract. 
In these latter cases there is a rupture of the capsule, either 
at the equator of the lens, or on its posterior or anterior 
surface. 

Within a few hours after a perforating injury of the 
anterior capsule, the lens substance in the immediate neigh- 
bourhood of the opening becomes opaque, swells, and pro- 
trudes as a grey fluffy-looking mass, through the opening 
in the capsule into the anterior chamber, where it gradually 
breaks up, dissolves, and becomes absorbed. It is immediately 
followed by other portions of the lens which have become 
cataractous, until, after many weeks, the whole lens will 
have disappeared, and the pupil again become black ; and the 
eye may see well, if a suitable convex lens be put before it. 
Marcus Gunn suggests, that the explanation of the solution 
of the cataract in the anterior chamber consists in the fact, 
that globulin is normally soluble in a weak solution of 
chloride of sodium, such as we have in the fluid of the 
anterior chamber. 

But the course of events just sketched is the most 
favourable one, and is hardly likely to take place in a case 
which is wholly untreated. In the first place the swelling 
of the lens — especially if, in consequence of a wide opening 
in the capsule, it be rapid — is liable to irritate the iris, and 
to cause iritis; or to push the periphery of the iris forwards 



464 



DISEASES OF THE EYE. 



[CHAP. XIV. 



against the periphery of the cornea, block the angle of the 
anterior chamber, and cause secondary glaucoma. 

Moreover, violent plastic or purulent uveitis may come on, 
as the consequence of the introduction of infective matter 
on the perforating object, or foreign body, which causes the 
cataract. Where this occurs, the case enters the category 
of diseases of the uveal tract ; and the cataract, as such, 
becomes a minor consideration. 

Again, we sometimes meet with traumatic cataracts which 
do not undergo any absorption process, but simply remain 
stationary ; or, in the course of years, they may undergo 
secondary changes, similar to those which occur in senile 
cataract. In these instances, the trauma is usually a blow 
on the eye, not a perforating injury : and it is believed that 
the rupture of the capsule closes soon after the blow, and 
hence no lens matter can escape into the anterior chamber ; 
also, the rupture in many of these cases is probably at 
the equator of the lens, where the aqueous would not readily 
get access to the lenticular substance. 

Occasionally, cataracts caused by blows on the eye (con- 
cussion cataracts) take the form of posterior polar cataracts, 
very similar to those seen sometimes with chorioiditis and 
retinitis pigmentosa (p. 461), the rest of the lens remaining 
transparent. These traumatic posterior polar cataracts 
sometimes clear up spontaneously. 

Where the cataract is produced by a small foreign body, 
which has passed through the cornea and into the lens, it 
is a matter of importance, for the prognosis, to decide whether 
the foreign body be in the lens, or have passed through it into 
the deeper parts of the eye. In the former case we may hope 
to extract it with the cataractous lens ; while in the latter 
case we must fear that it will set up dangerous inflammatory 
reaction. In such cases the lens should be well searched with 
focal illumination, and the transmitted light may also be of 
use; but it must be remembered that, in these traumatic 



CHAP. XIV.] 



THE CRYSTALLINE LENS. 



4G5 



cataracts, there are often glittering sectors in their deep 
parts, which may readily be mistaken for a metallic foreign 
body. If the foreign body be of steel or iron, the sideroscope 
may be employed for its detection, or, the Rontgen rays be 
utilised. 

Treatment. — The pupil should be kept dilated with atropine, 
in order to draw the iris out of the way of the swelling lens 
matter ; and nothing more is necessary if complications do 
not arise. But should iritis, or high tension, come on — and 
the surgeon must constantly test the tension — it is important, 
without further delay, to extract as much as possible of the 
cataract. This may be done either without an iridectomy, 
through a linear incision some 10 mm. long in the upper 
third of the cornea, or with an iridectomy, through an incision 
in the upper margin of the cornea. 

If a foreign body be present in the lens, extraction of 
the latter with the foreign body should invariably be 
undertaken. 

Where violent purulent or plastic uveitis is set up by the 
trauma, the treatment resolves itself into that required for 
these inflammations. 

*Operations for Cataract. 

With regard to the State of Health of the Patient about to 
be operated on it is desirable, as in every operation, that it 
should be good. Yet, we have so often in these cases to deal 
with very old people, that we cannot in every instance require 
sound organs and a robust constitution ; and, as a matter of 
experience, we have not found serious disease of the heart, lungs, 
and liver, even when they all existed in the same individual, 
any impediment to a successful operation. Diabetes is no 
absolute eontra-indication, although, as already stated, coma 
does sometimes ensue, and even in the presence of Bl ight's 
disease a successful operation may be performed. Very 

30 



4G6 



DISEASES OF THE EYE. 



[chap. xiv. 



advanced years form no obstacle. We have frequently 
operated for cataract on persons over eighty years of age, 
and always with success. 

The State of the Eye itself should be carefully investigated 
prior to proposing, or undertaking, an operation for cataract, 
and is a much more important matter than the general health. 
Above all things, it is to be determined whether there be 
intraocular complications, which would neutralise the result 
of a successful operation, such as detachment of the retina, 
disseminated chorioiditis, atrophy of the optic nerve, etc. The 
examination of the eye before the lens has become opaque, 
if the surgeon have had that opportunity, will be the most 
reliable basis upon which to go ; and, for this reason, a 
careful note should be taken of the condition of the fundus 
in each case of incipient cataract. The examination of the 
fuudus of the other eye, if its lens be clear, may help in 
determining the point, in so far as those intraocular diseases 
are concerned which are apt to be binocular. Again, the 
condition of the anterior capsule of the lens should be 
observed, for a defined glistening white square patch, about 
2 mm. broad, situated in the centre of the capsule, tells the 
tale of intraocular mischief. It cannot be confounded with 
the more diffused striated and punctated capsular alterations 
due to over-ripeness. 

Finally, the functions of the eye should be examined. With 
an uncomplicated cataract of the most opaque kind, good 
perception of light should be present, so that the light, say, 
of a candle some two metres distant may be distinguished. 
In less dense cataracts, fingers may be counted at 1 m. or 1"5 in., 
even when full maturity has been attained. The. field of vision 
must be examined by means of the ' projection ' of light — i.e., 
a lighted candle held in different parts of the field should be 
recognised by the patient, who is required to point his finger 
in the direction of the light, as it is moved rapidly from one 
part of the field to another. This examination can also be 



chap, xiv.] THE CRYSTALLINE LENS. 



467 



made by means of the light reflected from the ophthalmoscope 
mirror. If the patient fail to project the light in any direc- 
tion, a diseased condition in the corresponding part of the 
retina may be suspected. Yet, in cases of very old uncom- 
plicated cataract, the patients often project, the light in some 
one direction, no matter where it may come from. A certain 
degree of intelligence on the part of the patient is required 
for this test. 

By the foregoing means, most of the intraocular complica- 
tions of a serious nature can be detected ; but there is at least 
one against which there is no safeguard, namely, a small 
circumscribed spot of chorioido-retinal degeneration at the 
macula lutea (central senile chorioiditis). After removal of a 
cataract from an eye affected in this way, the patient's vision 
is so much improved as to enable him to go about alone, 
but reading will still remain an impossibility for him, and 
to that extent the result of the operation will be a 
disappointment to patient and surgeon. 

The Cornea should be Examined. — Such corneal opacities as 
would seriously compromise vision may contra-indicate the 
operation ; but slighter opacities, discernible only with oblique 
illumination, would merely diminish the future acuteness of 
vision, and would require a corresponding prognosis to be 
given before operation. 

The Condition of the Appendages of the Eye, too, must be 
examined. Should there be any conjunctivitis, blepharitis, 
or dacryocystitis, it ought to be cured or alleviated before 
the operation is undertaken. Very successful operations, 
it is true, may be performed in the presence of chronic 
dacryocystitis, or of granular ophthalmia ; but, the risk is 
great, and it is in all respects wiser to reduce their activity 
to a minimum. In cases of chronic dacryocystitis, extirpa- 
tion of the lacrimal sac is imperative, prior to a cataract 
extraction. 



468 



DISEASES OF THE EYE. 



[chap. xiv. 



Extraction of Cataract. 

*Linear Extraction. — The extraction through a linear in- 
cision in the cornea is applicable only to soft, or fluid, cataracts, 
in persons under the age of twenty-five. Tbe instruments 
required are :■ — A spring lid elevator, a fixation forceps, a 
wide keratome or a Grace's cataract knife, a cystotome, and 
a Critchett's vectis. 

The speculum having been applied, a fold of conjunctiva 
close to tbe margin of the cornea, and at tbe inner end of 
tbe horizontal meridian of tbe latter, is seized (Fig. 171) 




Fig. 171. 



with the fixation forceps, and the eye fixed by it through- 
out the operation. Tbe point of tbe keratome is now 
entered into the cornea in its horizontal meridian, about 
4 mm. from its outer margin, and is passed into the anterior 
chamber ; or, the incision may be made in the upper part of 
the cornea. The blade of the knife is then laid in a plane 
parallel to that of tbe iris, and pushed on until the corneal 
incision has attained a length of 6 or 7 mm. Tbe point 
of tbe knife being now laid close to the posterior surface 
of the cornea — in order that no injury may be done to 
the iris or lens when the aqueous humour commences to 
flow off — the instrument is very slowly withdrawn, so that 
the aqueous humour may come away gradually, without 
causing prolapse of the iris. In withdrawing the knife 



chap, xiv.] THE CRYSTALLINE LENS. 



4(59 



it is well to enlarge the inner aspect of one or other end 
of the wound, by a suitable motion of the instrument in that 
direction. 

The keratome being now laid aside, thecystotome is passed 
into the anterior chamber (Fig. 172) as far as the opposite 
pupillary margin, care being taken, by keeping the sharp 
point of the instrument directed either up or cfown, not o 
entangle lt in the wound or in the iris. The poin is tow 
turned directly on the anterior capsule, and, by withdrawing 




» then removed f ' m 1 T SP UCed - Th ° 
P-utions as on ^ "» ^ 

» h *> ^ntJe pressure beint ° t0 ^ S ° me - 

aspect of the ey h y \£ f* *PP«ed to the 

-7 the lens is evLuated !, ^ ^ * this 

f, " ite «■* the ope a " on i Tf* ^ h&S becom * 
^ first clear the n , C ° nClUded - If P"*™" do 
-moved, ^^T^' ^ ^uld 
-inutes allowed to apse L ' I "ST" and a *>w 

■* be secreted. A re^new"] of +i that some aqueous humour 

Probably no* £ * V T 8 t0 *« the 

* made, and then fre h att ' an ° ther P ause *V 

6Sh attem P fcS em P%ed until the pupU 



470 



DISEASES OF THE EYE. 



[chap. XIV. 



is quite clear. Ifc is unwise to insert the vec'tis into the eye 
to withdraw the fragments j and, if some of these should be 
left behind, no ill results need necessarily follow, although 
iritis is more apt to supervene than if the lens be thoroughly 
evacuated. Fragments left behind become absorbed. If 
there be a prolapse of the iris which cannot be reposed, it 
must be abscised. 

*The Three Millimetre Flap Operation, or, as it is more 

commonly called, The Combined Operation (i.e., combined 
with an iridectomy). We shall describe the operation as 
we are in the habit of performing it ; and, for success in 
the cataract operation, it is necessary, not only to select a 
rational method, but also to devote the utmost attention to 
a series of minute details in its performance. 

Preparation of the Patient. — A gentle purgative is given 
the clay before the operation, so that the bowels need not be 
disturbed for two days after the operation. The face is 
washed with hot water and soap, shortly before the operation. 

Preparation of the Eye. — Half an hour before the operation, 
a drop of a sterilised 2 per cent, solution of sulphate of 
eserine is dropped into the eye. Just before the operation, 
at intervals of two minvites, three drops of a sterilised 2 per 
cent, solution of hydrochlorate of cocaine are dropped into 
the eye. Finally, the lids having been everted, the conjunc- 
tival sac is thoroughly washed out with sterilised physio- 
logical solution of common salt, particular attention being 
paid to the fornix of each lid, and to the inner and outer 
canthus. Then the skin of the eyelids and immediate sur- 
roundings of the eye are freely washed with the same 
solution. 

Preparation of the Instruments. — Immediately before the 
operation, the instruments are sterilised by boiling ; and 
are then plunged for a moment into absolute alcohol, and 
laid on a sterilised porcelain tray, under a sterilised cloth, 
until required for use. 



CHAP. XIV. 1 



I'll K CRYSTALLINE LENS. 



471 



During the Progress of the Operation, small hits of sterilised 
lint, wet with the sterilised salt solution, are employed to wipe 
away coagula, cortical masses, etc., and are not employed 
a second time. An assistant should place the instruments 
in the surgeon's hand in their turn, and take out of his 
hand those he has used, in such a manner as to render it 
unnecessary for him to look away, even for a moment, 
from the field of operation. 

The Operation. — A spring wire lid-speculum is applied. 
The eye is fixed with a catch fixation-forceps by a fold of 
conjunctiva and subconjunctival tissue, below the vertical 
meridian of the cornea, or a little to one side of this line 
(Fig. 173). 

The point of the knife is entered just in the margin of the 
clear cornea, at the outer extremity of a horizontal line which 
would pass 3 mm. below the summit of the cornea. This line 
is easily found by placing the knife, which is about 2 mm. 
broad, horizontally across the cornea, so that a margin of clear 
corneal tissue 1 mm. broad may remain exposed between the 
knife and the summit of the cornea. The knife is then 
passed cautiously through the anterior chamber, and the 
counterpuncture is made in the corneal margin at the inner 
extremity of the horizontal line described, and the incision 
is then finished in the corneal margin by a few slow to- 
and-fro motions of the knife. 

While the incision is being made, the aqueous humour 
flows away, but, owing to the action of the eserine, the iris 
does not prolapse. The incision, hetween puncture and 
counterpuncture, lies in the clear cornea at its very margin, 
as represented by the dotted line in Fig. 173. 

The Second Stage of the Operation consists in an Iridectomy. 
The fixation of the eye having been given over to the assistant, 
the iridectomy is performed hy passing a curved iris forceps 
into the anterior chamber, seizing the smallest possible portion 
of the sphincter of the iris at a point corresponding to the 



172 



DISEASES OF THE EYE. 



[chap. xiv. 



centre of the incision, drawing it out, and with the forceps- 
scissors excising a very small central bit of iris. This should 
be done by approaching the forceps-scissors from over the 
cornea — i.e., at right angles to the wound — the iridectomy 
being thus made with one snip of the instrument, and, if care 
be taken to keep the blades close to the forceps, a narrow, 
neat coloboma will be obtained. By using a Tyrrell's hook, 
instead of a forceps, to draw out the iris, a narrow coloboma 
is obtained, and this stage of the operation is rendered less 
painful, as the pinching of the iris with the forceps causes 

pain. A small colo- 
boma, say of 2 mm. 
to 3 mm. in width, 
as in Fig. 160, is 
sufficient to allow 
of an easy delivery 
of the lens by 
doing away with 
the resistance of 
the sphincter iridis, 
and to prevent 
secondary prolapse 
of the iris {vide 
infra); and its advantages over a wide iridectomy, from 
an aesthetic point of view, are obvious. It should be 
the object of the surgeon to obtain the smallest possible 
coloboma. The procuring of a neat coloboma is much facili- 
tated if, prior to the operation, the pupil has been contracted 
(see Fig. 173) by the instillation of one or two drops of 
solution of sulphate of eserine, as above recommended. 

The Third Stage of the Operation is the Capsulotomy. 
The operator takes the fixation forceps from his assistant, 
who then raises the speculum and eyelids slightly off the 
globe, in order that no pressure may be exerted on the latter 
during the remainder of the operation. The surgeon, passing 




Fig. 173. 



chap, xiv.] THE CRYSTALLINE LENS. 



473 



the cystotome into the anterior chamber, divides the anterior 
capsule of the lens by two incisions, each from the lower 
pupillary margin upwards, one directed outwards, the other 
inwards, as far as the anterior surface of the lens can be 
seen, while finally a third incision is made along the 
upper periphery of the lens. An extensive opening in 
the capsule is of great importance, as otherwise difficulty 
in delivery of the lens may be experienced, and because a 
small opening renders the occurrence of secondaiy cataract 
more likely. In dividing the capsule it is important not 
to dig into the lens, as this, in the case of a hard cataract, 
is apt to dislocate it. A rather oblique application of the 
cystotome to the capsule is, for this reason, the best. 

The cystotome as it is withdrawn may pull a tag of the 
capsule into the corneal wound, where it lies until the end of 
the operation, and where, owing to its transparency, it may 
easily pass unnoticed. Such a tag acts as a foreign body, 
and may subsequently form the starting-point of troublesome 
complications. 

Capsule forceps have been devised for the purpose of 
taking away a large portion of the anterior capsule ; but this 
does not altogether obviate the clanger of capsule in the 
wound, nor does it do away with the likelihood of secondary 
cataract. The method has no advantages over that just 
described, in cases where the capsule is not thickened. But, 
when the anterior capsule is thickened, it is always desirable 
to tear away a central portion of it with forceps. 

The Fourth Stage is the Delivery of the Cataract. The 
eye is drawn gently downwards — the patient being called on 
to assist in this motion by looking towards his feet ; the 
spatula is placed just below the lower edge of the cornea, 
and gentle pressure is exercised on this place, the pressure 
being gradually increased, until the upper margin of the lens 
presents itself in the wound, when, the same pressure being 
maintained, the spoon is advanced over the cornea towards 



474 



DISEASES OF THE AY/:. 



[chap. xiv. 



the wound, pushing the lens before it and out through the 
wound. When the greatest diameter of the lens has passed 
the wound, the pressure of the spatula should immediately 
be diminished, lest rupture of the zonula be caused. The 
hxation-forceps and speculum are now removed from the eye, 
and a cold sterilised compress is laid on the closed lids. 

It may be noted that the fixation-forceps and the speculum 
are used until this late stage in the operation. Some 
operators employ neither fixation-forceps nor speculum from 
beginning to end of the operation ; while others discard the 
fixation-forceps when the corneal section is completed, but 
retain the speculum until after the iridectomy only, 
delivering the lens with the finger placed on the lower lid. 
The use of the hxation-forceps and speculum until after the 
lens is delivered gives more security and stability to the 
operator than the other methods, and it has no counter 
disadvantages. 

The Fifth Stage consists in Freeing the Pupil of any 
Cortical Masses which may have been rubbed off in the 
passage of the lens through the wound, and in what is called 
the Toilette of the Wound. 

The presence of cortical remains is recognised by the pupil 
not having become quite black, or by the vision not being 
such as it ought to be (fingers counted at several feet), or by 
inspection of the cataract just removed showing that some 
portions of it are left behind. The use also of focal electric 
illumination for the detection of cortical fragments is very 
advantageous. If any fragments be present, the cold sterilised 
compress having lain on the eye for a few minutes to enable 
some aqueous humour to collect, the operator, facing the 
patient, raises the upper lid with the thumb of the left hand, 
and then, with the first and second fingers of the right hand 
laid on the lower lid, he makes light rotatory motions with 
this lid over the cornea so as to collect the masses towards 
the pupil, and then with a few rapid light motions upwards, 



CHAP. XIV.] 



THE CRYSTALLINE LENS. 



475 



with the margin of the lid, these masses are driven towards, 
and out of, the wound. Care and delicacy of touch are 
required in order to perform this lid-manoeuvre successfully, 
without rupturing the hyaloid by undue pressure. 

With an iris-forceps the blood-clots which may adhere 
to the wound are now removed. 

To prevent the possibility of any portion of capsule — 
which may have been drawn into the wound by the cysto- 
tome, or pushed into it during delivery of the cataract — 
becoming incarcerated in the wound during healing, a 
bent iris-forceps is now passed open between the lips of the 
wound, closed, and drawn gently out again. Frequently a 
tag of capsule will have been captured by the forceps, and is 
snipped off with the scissors, or it may be that no capsule 
is caught. The forceps is then similarly inserted at an 
adjacent part of the wound ; and in this manner the wound 
is searched from end to end for capsule. 

Finally, the coloboma has to be seen to. The peripheral 
portions of the iris corresponding to the ends of the wound 
are apt to have become prolapsed in the course of the operation, 
and to have displaced the angles of the coloboma upwards. 
If this be not corrected, the prolapsed portions of the iris heal 
in the wound, and cause bulgings there later on, the pupil in 
the course of some months becoming drawn up towards the 
cicatrix. Hence, in every case, even where everything seems 
to be in order, it is important to pass the narrow spatula into 
the anterior chamber, and to gently stroke down each pillar of 
the coloboma as far as it can be brought. The instillation 
of eserine, which has been made before the commencement 
of the operation, will cause the sphincter iridis to assist in 
producing the desired result. All this is aptly termed the 
toilette of the wound. 

The sight of the eye should then be tested by finger count- 
ing, as this affords the patient satisfaction, and lends him 
courage for the next few days of strict quiet. Finally, 



476 DISEASES OF THE EYE. [chap. xiv. 



the conjunctival sac is flooded with the sterilised saline 
solution. 

The dressing is now applied. A piece of dry sterilised 
lint, sufficiently large to extend £ inch beyond the orbital 
margin in every direction, is laid on the closed eyelids. 
Pieces of sterilised absorbent cotton-wool are laid on this, the 
hollows at the inner canthus, etc., being carefully filled up ; so 
that, when the bandage is put on, it may exert equal and 
gentle pressure on every part of the eye. Three turns of a 
narrow roller bandage over the dressing and round the head, 
are applied ; but various other, and doubtless equally good, 
forms of bandage are in use. The pressure of the bandage 
need only be sufficient to maintain the dressing firmly in its 
place. The other eye is closed by a light bandage. 

We do not recommend the after-treatment of cataract 
operations without bandage, as advocated by some surgeons. 

Accidents liable to occur during the Operation. — The Wound 
may be made Too Short, and the delivery of the lens, con- 
sequently, may be so difficult that the margins of the wound 
become contused, and consequently suppuration may be 
promoted. The zonula, too, may be ruptured by the exces- 
sive pressure, from efforts to force the lens out through the 
narrow aperture, and prolapse of the vitreous may ensue. 
If the directions above given be carefully attended to, the 
vast majority of both hard and soft cataracts may be extracted 
without difficulty ; but should the wound be made too small, 
it can best be enlarged by the forceps-scissors, or a blunt- 
pointed knife made for the purpose. Where the presence of 
an unusually large hard cataract is diagnosed, it is important 
to make the incision larger ab initio, by placing puncture 
and counterpuncture nearer to the horizontal meridian of 
the cornea than above directed. 

Haemorrhage into the Anterior Chamber may take place. 
It may be from the iris, from the corneo-sclerotic mai-gin, or 
from the conjunctiva. Pressure with the spatula on the 



chap, xiv.] THE CRYSTALLINE LEXS. 



477 



cornea, which causes the wound to gape, is often successful 
in clearing the chamber of blood, which might interfere with 
accurate division of the capsule. Yet, when this cannot be 
completely got rid of, the capsulotomy can be performed by 
the exercise of greater care. Adrenalin dropped into the eye 
aids in arresting the bleeding. 

Prolapse of the Vitreous Humour. This accident may 
be caused by undue pressure made on the eyeball by the 
speculum, fixation forceps, or spatula, or by the lower 
lid during the lid-manoeuvre. It may be due to defective 
zonula with fluid vitreous humour. When the vitreous 
prolapses prior to delivery of the lens, the latter falls back 
into the eye, and can only be delivered by at once drawing 
it out with a Oritchett's, Taylor's, or other suitable vectis ; 
and this must be regarded as one of the most serious 
accidents which can occur in the course of the operation, for it 
is often impossible to reach the lens without doing much 
damage to the eye, as a result of which sight may be lost. 
Loss of vitreous after delivery of the lens is less serious ; 
indeed, a considerable portion of the vitreous may then be lost 
without ill result to the eye ; yet it increases the trauma- 
tism, and renders inflammatory reaction more liable to occur. 
Opacities in the posterior chamber of the eye are frequently 
an ultimate result of loss of vitreous; but a much more serious 
consequence is sometimes seen in detachment of the retina. 

Normal After-Progress. — Soon after the completion of a 
normal operation, the effect of the cocaine having passed off, 
some smarting commences, and continues for four or five hours. 
After that time, the patient has no unpleasant sensation in 
the eye, unless it be some itching, or a slight momentary 
pain, or sensation of a foreign body, especially when the eye 
is moved under the bandage. The first dressing is made in 
forty-eight hours, in a manner similar to that immediately 
after the operation, a drop of atropine being instilled, as also 
at each successive dressing ; and the sterilised salt solution 



478 



DISEASES OF THE EYE. 



[chap. xiv. 



is vised for freely washing the margins of the eyelids, some 
of it being allowed to trickle into the conjunctival sac. At 
this first dressing, it is well to abstain from a very minute or 
lengthened examination of the eye ; but, if the lid be gently 
raised, the wound will be found closed, the cornea clear, the 
anterior chamber completely restored, and the pupil semi- 
dilated and black. The subsequent dressings are made night 
and morning, for the purpose of instilling atropine. On the 
third day after the operation the patient may be allowed to 
sit up, the room being kept moderately dark ; and on the 
fifth or sixth day the bandage may be left aside permanently, 
and dark glasses worn in its stead. In the course of a few 
days more the patient, having been gradually used to more 
light, may be allowed out of doors. It is desirable to continue 
the use of atropine for about a fortnight longer, or until 
all abnormal vascular injection of the white of the eye has 
disappeared, as until then there is danger of iritis. (For 
selection of glasses in aphakia see end of this chapter.) 

Irregularities in the Process of Healing. — The pain may con- 
tinue longer than four or five hours, and it is then well to quiet 
it by a hypodermic injection of morphia in the corresponding 
temple. Should severe pain come on some hours later, it is 
apt to be due to an accumulation of tears under the eyelids, 
and it immediately subsides on the bandage being removed, and 
exit given to the tears by slightly opening the eye. 

Late Appearance of the Anterior Chamber. At the first 
dressing it will sometimes be found that there is no anterior 
chamber, although the appearance of the wound is quite 
satisfactory ; but this need occasion no alarm, as the anterior 
chamber is sometimes not restored for a week. Should a 
more lengthened absence of the anterior chamber be noticed, 
it may be due to the presence of a small tag of capsule, or 
a small portion of iris, in the wound, and it is then desirable 
to search the latter with a forceps, and to cut off any capsule 
or iris which may be found there. 



chap, xiv.] TEE CRYSTALLINE LENS. 



Striped Keratitis. At the first dressing, also, 
sometimes be observed that there is a more or less well- 
marked striated cloudiness of the cornea, extending over 
nearly the whole of it, or occupying only a part in the 
immediate neighbourhood of the wound. This opacity is 
held by some to be the result of injury to the endothelium 
of the posterior surface of the cornea during the operation. 
It is this endothelium which protects the cornea from 
being infiltrated by the aqueous humour, and the appear- 
ance we call striped keratitis is caused by ccdema of the 
cornea. According to another explanation, striped 
keratitis is due to folding of the posterior layers of the 
cornea, on account of the difference in tension in the 
vertical and horizontal directions. Striped keratitis is, for 
the most part, of no serious import, as it usually passes 
away in a few days, and leaves the cornea perfectly clear. 

Suppuration. With careful aseptic measures this is a 
rare event. When it occurs, it usually does so between the 
twelfth and thirty-sixth hour after the operation, rarely earlier 
or later, and is very serious ; for, in the vast majority of 
cases, do the surgeon what he may, it leads to loss of the 
eye. Its onset is usually made known by severe pain of a 
continuous aching kind in and about the eye ; and it is thus 
easily distinguished from the slight, short, stab- 
bing pain, with long intermissions, which some 
patients complain of, and which has no evil 
import. On removing the bandage the eye will 
be found full of tears, and the wound covered 
with a layer of muco-pus, which can be removed with the 
forceps in one mass, while the aqueous humour and cornea 
may already present some opacity. In some hours more, 
the corneal opacity increases considerably, the iris becomes 
distinctly inflamed, and the pupil filled with a mass of 
inflammatory exudation. In many instances the attack com- 
mences as septic iritis. The inflammatory process may remain 



it 




480 



DISEASES OF THE EYE. 



[chap. xiv. 



confined to the wound and iris, and when, in the course of 
some weeks, it entirely subsides, it leaves the pupil drawn up 
towards the wound, so that an appearance as in Fig. 174 
is presented. Or, the inflammation may strike into the 
ciliary body and chorioid, and produce purulent panophthal- 
mitis, with total destruction of the eye. Or, the inflamma- 
tion may be of the plastic type, leading to destruction of 
the eye, and threatening the other eye by sympathetic 
ophthalmitis. 

* To combat Suppuration the best method is the immediate 
cauterisation of the corneal wound, if it be the seat of 
the process, in its whole extent with the galvano-cautery. 
Also, the wound may be opened up from end to end with a 
spatula, the aqueous humour evacuated, and the anterior 
chamber washed out with injections of sublimate solution 
1 in 10,000, while the conjunctival sac is irrigated with 
the same solution. If necessary these measures are to 
be repeated at intervals of eight or ten hours. Subcon- 
junctival injections of solution of sublimate 1 in 2,000, 
or of oxycyanide of mercury 1 in 5,000, are often of use 
in these cases, if they be commenced very soon after the 
onset of the attack. Half a c.cm. is to be injected as 
far back as possible under the conjunctiva once, or even 
twice, in twenty-four hours. From four to eight injections 
are usually needed according to the severity of the case. 
Intense chemosis is caused. To relieve the paiu of the 
injection, five drops of a 1 per cent, solution of acoine may 
be added to the quantity of oxycyanide of mercury solution 
injected, or to the sublimate injection a few drops of 2 per 
cent, cocaine solution. But very severe radiating pain 
usually comes on a quarter of an hour later, and continues for 
several hours. Hot fomentations afford some relief from 
this pain. The patient should be confined to bed, and the 
eye bandaged. 

Iritis. A few days after the operation iritis, sometimes 



chap, xiv.j . THE CRYSTALLINE LESS. 



481 



of a severe type, may come on. It, too, must be reckoned 
as due to infection during the operation, especially if some 
lens-substance have remained, for the latter is a favourable 
nidus for the cultivation of infective material. The in- 
flammation is ushered in with the usual symptoms of pain, 
and is generally of the plastic variety. General plastic 
uveitis may ensue, and sympathetic uveitis may result. 
Treatment consists in strict confinement to a dark room, with 
atropine, and sub-con junctival mercurial injections, and 
quinine or salicylate of soda internally. 

Detachment of the Chorioid. Fuchs has pointed out, 
that detachment of the chorioid occurs some days after 
cataract extraction, in some of those cases in which the 
anterior cbamber does not form ; or in which, having formed, 
it becomes empty again. The detachment occurs, too, occa- 
sionally after iridectomy unconnected with cataract extrac- 
tion. It can be seen with the ophthalmoscope, and 
sometimes even with focal illumination. Vision while 
the lesion is at its height is seriously affected, but the 
prognosis is good, for the detached portion always becomes 
reposed. 

C'ystoid Cicatrix. After convalescence, the cicatrix in 
the corneal margin sometimes becomes prominent and 
semi-transparent, presenting the appearance of a vesicle, 
and may attain a large size. The extremities of the 
incision are the most common positions for this condition, 
but it may occupy the entire length of the cicatrix. 
It does not generally appear for some weeks, or more, 
after the operation. In some cases it is caused by a 
tag of iris which is incarcerated in the wound ; but in other 
cases by a small piece of capsule, which has similarly healed 
in the wound. Irregularity in curvature of the cornea, and 
consequent irregular astigmatism, are the least of its evil 
consequences. If the condition be caused by incarceration 
of iris, the pupil will be gradually drawn close to the upper 

31 



•»S2 DISEASES OE THE EVK ■ [cirAP. .\1V. 



corneo-sclerotic margin ; while, if it be caused by a portion of 
capsule, irido-cyclitis may be produced. Whether the iris or 
the capsule be the cause, these eyes are always exposed to the 
danger of a sudden onset of purulent irido-chorioiditis (see 
p. 370). All this demonstrates the immense importance of 
attention to those details of the operation, which are calcu- 
lated to obviate incarceration of iris, or of capsule, in the 
cicatrix. 

* Cataract Extraction without Iridectomy, or, as it 

is more commonly termed, The Simple Operation. — This 
method differs from the Combined Operation, in that the 
incision occupies a greater extent (about one-third) of the 
circumference of the cornea, and lies in the corneo-scleral 
margin just outside the clear cornea, and that no iridectomy 
is made. The round pupil, and consequent prettier appear- 
ance of the eye, and the diminished tendency to loss of 
vitreous, and to incarceration of the capsule, are the advan- 
tages this procedure has over the Combined Operation as 
above described ; for, vision with a circular pupil is not 
better, than where a narrow iridectomy has been made. 

On the other hand, the extraction without iridectomy 
exposes the eye to the serious daDger of prolapse of the iris 
into the wound some hours, or days, after the operation. 
An iridectomy must be made in all cases in which the iris 
cannot be satisfactorily reposed after delivery of the lens. 
These are, however, few in number. But, even when the iris 
can be well reposed, security against the occurrence of a 
prolapse within the first two or three days after the operation 
is not obtained ; nor does eserine, nor any other means, provide 
the desired safeguard. Prolapse of the iris does take place 
after a number of these operations, and there is no means 
of foretelling in what eyes it will occur. The prolapsed 
portion of iris heals in the wound, which then, in a few 
weeks, becomes more or less cystoid ami bulging, causing 
displacement of the pupil and irregular curvature of the 



chap, xiv.] TIH-: CRYSTALLINE LENS. 



■J 83 



cornea, with resulting deterioration of vision. Nor is this 
all ; for such eyes are liable — weeks, months, or even years 
after the operation— to take on severe irido-cyclitis, ending 
in total loss of sight. Another disadvantage of the operation 
is. that removal of cortical remains cannot be so effectually 
performed, as where a coloboma has been made. 

The more peripheral position of the incision (corneo- 
scleral margin) somewhat reduces the tendency to iris- 
prolapse, and gives rise to less astigmatism than does an 
incision in the clear cornea. 

Why it is that in the simple extraction, prolapse of the 
iris with subsequent incarceration is more liable to occur, 
even some days after the operation, than in the combined 
operation, and why it is so difficult to devise a sure means 
for preventing the accident, as, also, how even a very 
narrow coloboma is, almost always, sufficient to protect 
the eye from this accident, is as follows : — Within a few 
hours after the operation the wound in the corneal margin 
commonly closes, the aqueous humour collects, and the an- 
terior chamber is restored. But it takes many hours more 
for the delicate union of the lips of the wound to become 
quite consolidated, and during this time it requires but 
a slight thing — a cough, a sneeze, a motion of the head, the 
necessary efforts in the use of a urinal or bed-pan, no 
matter how careful the nursing — to rupture the newly 
formed union ; and, as a matter of fact, this often does 
take place. The aqueous humour then flows away through 
the wound with a sudden gush, and, wbere the simple 
extraction has been employed, carries with it the iris. 
It is that portion of the aqueous humour which is 
situated behind the iris, which is chiefly concerned in 
the iris-prolapse ; the aqueous humour in the anterior part 
of the anteiior chamber probably flows off without in- 
fluencing the position of the iris. 

The formation of even a narrow coloboma prevents pro- 



DISEASES OF THE EYE. 



[chap. xiv. 



lapse of the iris when the wound bursts, but this is not 
because the portion of iris which is liable to prolapse has 
been taken away, for that would be nothing less than the 
whole of that part of the iris which corresponds to the length 
of the wound. The coloboma averts secondary iris-prolapse, 
by providing a way for the aqueous humour contained in 
the posterior part of the anterior chamber to escape directly 
through the wound, without carrying with it the iris in its 
rush; and the narrowest coloboma which can be formed is 
amply sufficient for the purpose. 

As to disfigurement of the eye resulting from the 
combined operation, there is practically none, when the 
coloboma is narrow, and is situated in the upper part 
of the iris. The pupil, too, is movable, almost, if not 
quite, as much so, as in most cases of simple extraction ; 
for a narrow coloboma does not render the pupil immovable. 
Where there are no adhesions between the pupillary margin 
and the capsule, as frequently happens, the reaction to light 
is active, a drop of atropine will dilate the pupil widely, and 
a drop of eserine will contract it. 

* Extraction in the Capsule.— The ideal cataract 
extraction is that in which the opaque lens in its capsule is 
removed, thereby obviating all subsequent trouble due to the 
capsule ; namely, incarceration in the wound and secondary 
cataract. The serious objection to the method, which has 
prevented it from coming into general use, is the great danger 
of prolapse of vitreous which must attend it, owing to the 
liability of the hyaloid membrane to be ruptured during 
delivery of the cataract. The operation has been performed 
by ophthalmic surgeons from time to time, but has recently 
been specially cultivated in India by Major Henry Smith. 
His incision lies in the cornea about 3 mm. below its upper 
margin, the puncture and counter-puncture being in the 
corneo-scleral margin, as peripherally as possible. The 
speculum is then removed, and the assistant raises the upper 



chap. XIV.] THE CRYSTALLINE LENS. 



485 



lid with a strabismus hook, and draws the under lid down 
with his finger. The curve of a strabismus hook is placed 
on the cornea in its lower third, and a Daviel's spoon just 
above the upper edge of the wound. With these instru- 
ments gentle pressure and counter-pressure is made, until the 
lens is more than half delivered ; it is then tilted with the 
hook, and the delivery is completed. The operation may 
be done with or without iridectomy, but must be performed 
slowly and cautiously, else the lens capsule may be ruptured, 
and the object of the method frustrated. Major Smith, in 
a large number of cases, had loss of vitreous in only 
6 6 per cent. 

* Mental Derangements after Cataract Extractions. — After 
cataract extractions, during the period of confinement to bed, 
passing mental disturbances are sometimes seen in old 
people. This usually takes the form of confusion of ideas, 
hallucinations, and terror. It is hard to assign a cause for 
it, but probably it is mainly due to the quiet, and to the 
exclusion of light if a binocular bandage have been applied, 
following on a period of some anxiety and excitement. A 
few doses of sulphonal, and permission to sit up — at least 
in bed — with removal of the bandage from the unoperated 
eye, will be the best measures to adopt in such a case ; and 
speedy restoration of mental equilibrium may be looked 
for with confidence. Care should be taken not to mistake 
the symptoms of atropine poisoning for this form of mental 
disturbance. 

* Secondary Glaucoma after Cataract Extraction occurs now 
and then, by whatever method the extraction may have been 
performed. This is contrary to what one would have ex- 
pected, in view of the diminished contents of the globe, 
by reason of absence of the lens, and especially where an 
iridectomy has been made. High tension in these instances 
may come on soon after recovery from the cataract operation, 
or after a good result has existed for many years. Treacher 



■186 



DISEASES OF TEE EYE. 



[CHAP. XIV. 



Collins' microscopic investigations show that in these cases 
either the iris, the capsule, or the hyaloid has become 
entangled in the wound, and incarcerated in the subsequent 
cicatrix, and it seems that this leads in some cases to closure 
of the filtration angle in its entire circumference. Collins 
says : In all eyes in which glaucoma comes on after extrac- 
tion of cataract, there is adhesion to or entanglement of the 
lens capsule in the extraction scar. This adhesion or entangle- 
ment keeps the root of the iris — or the most anterior of the 
ciliary processes, if the iris have been removed up to the 
periphery — in close contact with the back of the cornea in the 
region of the coloboma, and so keeps the angle of the 
chamber blocked in that situation. The advanced position 
which the capsule takes, by reason of its attachment to 
the cornea, draws forward the iris lying in front of 
it, and in this way approximates the root of the iris, 
elsewhere than in the region of the coloboma, to the 
periphery of the cornea. In some cases, especially in those 
in which the extraction scar is very corneal, the advance in 
the position of the capsule is so great, that apposition 
of the cornea and iris is actually occasioned. In such 
cases, the increased tension follows as soon as the wound 
has closed after the operation. The adhesion of the lens 
capsule to the extraction scar is sometimes composed of 
inflammatory exudation ; this, on organising and contracting, 
tends gradually to advance more and more the position of 
the capsule, and consequently that of the iris. Such a 
gradual advance would explain those cases, in which the 
increased tension does not make its appearance, until some 
time after the cataract has been removed. 

Other authors have observed that in some, at least, of 
these cases, the anterior chamber becomes lined with 
epithelium which has grown in from the operation wound, 
and has blocked the angle of the anterior chamber. 

A wide iridectomy, or a sclerotomy, should be made as soon 



chap, xiv.] THE CRYSTALLINE LENS. 



as possible after the high tension shows itself, and by this 
means many of these eyes may be saved. Simple division of 
the capsule has produced a good effect in some cases. 

* Erythropsia after Cataract Operations. For an account 
of this see chap. xx. 

* Secondary Cataract. — The term secondary cataract, as 
here employed (compare p. 461), usually means a closure of 
the opening which is present in the anterior capsule 
after the removal of a cataractous lens, with a thicken- 
ing of the capsule in some of the cases, whereby an 
impediment is offered to the rays of light in passing 
through the pupil. The thickening may have pre existed 
in the capsule, or it may be due to subsequent pro- 
liferation of the epithelial cells on the inner surface of 
the capsule. The term is also used with reference to those 
cases in which no central opening has been made in the cap- 
sule (peripheral capsulotomy), and where the latter causes 
imperfect vision. It is also used in those cases where, after 
cataract extraction, an exudation in the pupil, consequent 
upon iritis, has occurred. Finally, and very incorrectly, it 
is applied to the cases which Fig. 174 represents, in which, 
after suppuration of the wound with irido-cyclitis, the iris 
is dragged upwards, and the pupil is consequently obliterated. 

The most simple form of secondary cataract occurs as a 
very fine cobweb-like membrane—the capsule of the lens — 
extending over the whole area of the pupil, which can often 
only be discovered by careful examination with oblique 
illumination. It may not cause any trouble of vision until 
some months after the extraction, when a little thickening of 
it may have taken place. 

Capsulotomy, as the operation for making a clear opening 
in the membrane is called, is best performed with a 
Knapp's needle-knife. This instrument has a blade 4^ mm. 
in length. It cuts on one side only, and the blade and 
the evenly rounded shaft are so proportioned, that the 



DISEASES OF TEE EYE. 



[chap. xiv. 



shaft fills exactly the opening made by the blade, and 
consequently the needle can be moved within the anterior 
chamber in every direction, without escape of aqueous 
or bruising of the cornea. The instrument must be of the 
utmost sharpness in point and edge, so that it may cut, 
and not tear. The point of the needle-knife is entered 
through a thin part of the capsule, and an opening is cut 
in it, hard and inelastic bands being avoided. 

Iridotomy is the operation used for the cases as in 
Fig. 174, where the iris forms a complete and tightly 
stretched curtain across the pupil. A vertical incision 
having been made in the cornea, about 3 mm. long, and 
the same distance removed from its inner margin, the 
closed blades — one of which has a sharp point — of de 
Wecker's forceps-scissors are passed into the anterior 
chamber. The blades are then opened, and the sharp 
point of one of them is forced through the stretched iris, 
and some 3 or 4 mm. behind it. By closing the blades 
the tightened iris fibres are cut across, and on their 
retraction a central clear pupil is formed in the iris and 
retro-iridic tissue. 

* Discission means the tearing of the anterior capsule 
of the lens with a needle, so as to give the aqueous 
humour access to the lenticular fibres, which causes them 
to swell, and gradually to become soft, and then to be 
absorbed. The larger the capsular opening, the more 
freely is the aqueous brought in contact with the lens, and 
the more rapid is its swelling. The rapidity of the swelling 
and absorption depend, also, on the consistence of the lens. 
The softer it is the more rapid is the process, the completion 
of which may require from a few weeks to many months. It 
is wise to make the first discission of moderate dimensions, 
in order to test the irritability of the eye, especially in 
adults. 

The instruments required are a spring speculum, a fixation- 



chap, xiv.] THE CRYSTALLINE LENS. 



489 



forceps, and a discission needle. The pupil is to be dilated 
with atropine. 

The eye having been cocainised, the speculum applied, 
and the eye fixed close to the inner margin of the 
cornea, the needle is passed perpendicularly through the 
cornea in its lower and outer quadrant, at a point corre- 
sponding to the margin of the dilated pupil. It is then 
advanced upwards to the upper margin of the pupil (Fig. 175), 
where it is passed into the capsule, but not deeply into the 
lens, and a vertical incision is effected by withdrawing the 
instrument slightly. If an extensive opening in the capsule 
be wished for, a horizontal incision can be added to the vertical 
one by a corresponding motion of the needle. During these 
manoeuvres the cornea, at 
the point of puncture, 
must form the fulcrum 
for the motions of the 
instrument. The instru- 
ment is then withdrawn 
from the eye, and some 
aqueous humour escapes 
through the opening. 
Atropine is instilled, and 
the bandage applied. 
The patient is kept in bed for a day. and then the bandage 
may be dispensed with, and dark spectacles worn. The 
iris is to be kept well under the influence of atropine, 
until the absorption of the lens is completed. Repetition 
of the operation is called for, if the opening be so small 
as to admit of but a very slow absorption of the lens, 
or if, as sometimes happens, the opening should close. 

This method is applicable to all complete cataracts up to 
the twenty-fifth year of age, and to those lamellar cataracts 
up to the same age in which the opacity approaches so close 
to the periphery of the lens, that pothing can be gained by 




•190 



DISEASES OF THE EYE. 



[CHAP. XIV. 



an iridectomy (p. 459). After the above age, the increasing 
hardness of the nucleus, and the increasing irritability of 
the iris, render the method unsuitable. 

Discission is a safe procedure, when used with the above 
indications and precautions. The danger chiefly to be feared 
is iritis, from pressure on the iris of the swelling lens masses. 
When this occurs, or is threatened, removal of the cataract by 
a linear incision in the cornea should be at once performed. 

Another danger consists in glaucomatous increase of tension 
(secondary glaucoma), which may come on without any sub- 
jective symptoms — although severe pain usually attends it — 
while the absorption of the lens still runs its proper course. 
It may happen, consequently, that, when absorption of 
the cataract is completed, the eye will be found blind 
from glaucoma. Frequent testings of the tension of the 
eye during the cure are therefore a most important precaution. 
Should the tension rise, removal of the lens through a linear 
incision in the cornea is at once indicated. 

* Dislocation of the Crystalline Lens.— This may be 

congenital (p. 491), or it may be the result of disease, such, 
for example, as anterior sclero-chorioiditis ; or it may be 
caused by a blow on the eye. 

The dislocation clue to disease or trauma may be partial 
or complete. Partial dislocation is often so slight as to 
be discoverable only when the pupil is widely dilated, 
the margin of the lens becoming then visible, by aid 
of the ophthalmoscope mirror, as a curved black line in 
some one direction ; or, the displacement may be so great 
as to bring the margin of the lens across the centre of the 
undilated pupil, in which case one part of the eye will be 
highly hypermetropic, while in another part it will be myopic. 
Complete dislocation may take place into the anterior chamber, 
into the vitreous humour, or even under the conjunctiva, if 
the sclerotic have been ruptured. 

The symptoms in partial dislocation are those of loss of 



CHAP, xiv.] THE CRYSTALLINE LEXS. 



491 



power of accommodation, and monocular double vision. Irido- 
donesis {i.e., trembling of the iris when the eye moves) is 
present, as a rule, in consequence of the loss of support 
provided for the iris by the lens. In complete dislocation 
the symptoms are those of aphakia — i.e., extreme hyper- 
metropia, and want of power of accommodation. 

Treatment. — In partial dislocation it is rarely that any treat- 
ment can be of service. The prescribing of spectacles suited, 
so far as it is practicable, to the faulty refraction is indicated. 
In complete dislocation of the lens into the anterior chamber, 
its extraction is usually required, especially if it cause 
symptoms of irritation. Dislocation into the vitreous 
humour is generally unattended by irritation ; but when 
the latter does arise, removal of the lens by aid of a spoon, 
through a peripheral corneal incision, has to be attempted. 

* Congenital Defects of the Lens. Congenital Cataract. 
(See pp. 458, 459, 460.) 

Ectopia of the Lens (Congenital Dislocation). — This is often 
hereditary, and often present in more than one member of 
a family. The displacement is more frequently in an 
upward direction than in any other. It is usually in both 
eyes of the patient. It is due to a mal-development of the 
zonula of Zinn, which in these cases is shorter in the 
direction towards which the lens is luxated. Discission or 
extraction are not indicated here. Occasionally some 
advantage is gained for vision, by the correction with glasses 
of one or other portion of the doubly refracting eye. 

Coloboma of the Lens. — Coloboma of the lens often co- 
exists with coloboma of their is (p. 409), but may be present 
alone. It is generally in the lower periphery of the lens. 

I^enticonus. — This is a rare congenital anomaly of the 
lens, in which its anterior surface, or, still more rarely, its 
posterior surface is cone-shaped. The derangements of 
vision are very similar to those caused by conical cornea. 

Aphakia (a, jn-iv. ; 0a/fo<?, a lentil, lens), or Absence of 



492 



DISEASES OF THE EYE. 



[CHAP. XIV. 



the Crystalline Lens. — The condition of the emmetropic eye 
after the removal of a cataract is one of high hypermetropia, 
and the power of accommodation is wanting. Consequently, 
in order that the eye may have the best possible sight for 
distant objects, a high convex glass has to be experimentally 
found to suit it, and stronger lenses must be prescribed for 
shorter distances. 

The degree of vision obtained varies considerably in different 
cases ; frequently V = * is obtained, but V = may be 
regarded as a satisfactory result ; and even lower degrees, 
which enable the patients to find their way about with com- 
fort, are classed as successful operations. The vision often 
improves for some months after the operation, patients who 
at first had only T 6 ff , or so, advancing up to f or f . For reading, 
writing, etc., at about 25 cm., a still higher convex glass must 
be provided. If the correcting lens for distant vision be + 10 D, 
its power, for the purposes of vision at 25 cm., must be 
increased by the lens which would represent the amplitude 
of accommodation from infinite distance up to 25 cm. This 
lens is 4 D (because V 0 ^ = 4) ; therefore + 14 D is the lens 
required. With these two lenses most patients are satisfied. 
For distinct vision at middle distances, they learn to vary 
the power of the lenses by moving them a little closer to, 
or farther from, the eye ; but, if necessary, a lens can be 
prescribed for distinct vision at any desired distance. 

In the case of hospital patients, one is often obliged to select 
the -f- glasses a fortnight or three weeks after the operation, 
but the result is more satisfactory when the selection can be 
postponed for six weeks or two months. Permanent wearing 
of the + glasses should not be permitted until all redness of 
the eye has passed off, and this varies in different cases. Until 
then, also, dark protection spectacles should be worn. 

In the majority of cases, after cataract operations, the best 
vision is not obtained until a certain degree of astigmatism 
is corrected. This astigmatism is caused by a flattening of 



chap, xiv.] THE CRYSTALLINE LENS. 



493 



the vertical meridian of the cornea, clue to the incision at 
its upper margin, and hence it is against the rule (see p. 72). 
An obliquity in the incision often produces an obliquity in 
the principal meridians of the astigmatism. The degree of 
astigmatism varies, and may be very high. It rapidly reaches 
its maximum after the operation, and then gradually dimin- 
ishes for weeks or months, and in some cases completely 
disappears; hence it is, that glasses for permanent use can 
be better prescribed a month or two subsequently to the 
operation. 



CHAPTER XV. 



* DISEASES OF THE VITREOUS HUMOUR. 

Purulent Inflammation of the Vitreous Humour (to 

which, unfortunately, the name pseudo-glioma is sometimes 
applied) occurs only as the result of perforating injuries, or 
of the lodgment of a foreign body, or as an extension of a 
purulent process from the chorioid (p. 370). 

Ophthalmoscopically, a purulent deposit in the vitreous 
humour gives a yellowish reflection, when light is thrown 
into the eye with the ophthalmoscope mirror, or on 
examination with oblique light. It is to be distinguished 
from a somewhat similar appearance in glioma of the retina, 
by the history, by its early complication with more or less 
severe iritis, by the very frequent retraction of the periphery 
of the iris, with bulging forwards of its pupillary part, and 
by the diminished tension of the eye, while a lobulated 
appearance is not so usual in it as in glioma. Again, in 
glioma the vitreous humour remains clear, while in this 
disease it is hazy. 

The condition, if at first confined to the vitreous humour, 
soon extends to the surrounding tissues, and usually leads to 
panophthalmitis and complete destruction of the eye. 

* Inflammatory Affections of the Vitreous Humour, 
other than the purulent form, are for the most part the 
consequence of diseases of the chorioid (including those 
which accompany high myopia p. 57), ciliary body, or retina, 
and display themselves as opacities of various kinds. These 
are either cells derived from the primarily diseased tissue, or 

494 



OHAP.xv.] THE VITREOUS HUMOUM. 



496 



they are secondary changes (connective tissue development) 
in the vitreous humour, the result of the cellular invasion. 

The chief Varieties of Vitreous Humour Opacities are : — 
(1) The Dust-like Opacity so characteristic of syphilitic disease 
of the retina and chorioid. It may occupy the entire vitreous 
humour, but is frequently confined to the region of the 
ciliary body, or to that of the posterior layers of the vitreous 
humour. (2) Flakes and Threads. These occur with chronic 
affections of the chorioid or ciliary body, and may be the 
result also of haemorrhages into the vitreous humour. They 
invade every portion of the humour. (3) Membranous 
Opacities, which are rare, and are probably the result either 
of extensive hemorrhagic extravasations or of chorioidal 
exudations. 

Most of the alterations in the vitreous humour are 
attended with, or give rise to, fluidity of it, or Synchysis. 1 

The Diagnosis of opacities in the vitreous humour is made 
with the ophthalmoscope mirror and a not very bright light, 
or with the plane mirror. If a very bright light and a 
concave mirror be employed, the finer opacities will not be 
readily seen. The pupil being illuminated, the patient is 
directed to look rapidly in different directions, when the 
opacities will be seen to float across the area of the pupil, as 
they are thrown from one side of the eye to the other 
in the fluid vitreous. 

Opacities in the vitreous can be distinguished from those 
in the lens by the fact that the latter are fixed, and are 
arranged mostly in a radiating manner. 

Another and very fine method for the detection of 
delicate opacities in the vitreous consists in placing a high 
+ lens, say -f 10 D, behind the ophthalmoscope mirror, and 
then going close to the eye, as in the. examination of the 
upright image. Minute opacities will then be seen as black 
dots floating in the vitreous humour. 



1 avf, together ; to jjour. 



496 



DISEASES OF THE EYE. 



[chap.' xv. 



The ophthalmoscope does not always detect changes in the 
chorioid or retina, when there are opacities in the vitreous j 
and in many such cases we are led to the belief, either that 
the diseased changes in the chorioid or retina are too fine to 
be seen with the ophthalmoscope, or that they are situated 
in the region of the ciliary body which is out of view. 

Vision is affected by opacities in the vitreous humour in 
proportion to their density, and to the extent to which the 
vitreous humour is occupied by them. The patients often 
observe them as floating positive scotomata in their field 
of vision. These entoptic appearances are caused by the 
shadows of the opacities thrown on the retina. 

The Prognosis depends on the cause of the opacities. 
The dust-like opacities accompanying specific retinitis are 
favourable for absorption, while the flake and thread 
opacities, frequently remain as permanent obstructions. 
Moreover, by shrinking, many of the more organised opacities 
give rise to detachment of the retina from the chorioid, and 
consequent blindness. 

Treatment consists, above all, in that for the exciting 
cause. Besides this, Heurteloup's artificial leech, or dry 
cupping on the temple, is useful ; and in many cases, 
soon after the application, a marked clearing up of the 
vitreous is apparent. 

Sub-conjunctival injections of a 4 per cent, sterilised 
solution of chloride of sodium are valuable in clearing up 
opacities in the vitreous humour, in many chronic or sub- 
acute cases. They are not used if there be acute uveitis 
present. Ten to twenty minims are injected, the point of 
the needle being entered far back near the fornix, towards 
which the injection is made. The inclusion of 5 minims of 
a 1 per cent, solution of acoin in the injection lessens the 
subsequent pain, which is often severe ; but, by some, the 
acoin is held to increase the tendency to inflammatory 
sequela? of the injection, such as cicatrices of the conjunc- 



chap, xv.] THE VITREOUS HUMOUR. 



497 



tiva, and adhesions of the latter to the sclerotic. Hot 
fomentations to some extent relieve the severe pain. The 
injection is repeated after a day or two, when the swelling 
and irritation have subsided. Usually not more than two 
or three injections can be given in a week. 

Injections of sublimate solution, 1 in 5000 to 1 in 2000, 
or of oxycyanate of mercury solution, 1 in 5000 — of which 
5 to 10 minims with one or two minims of 1 per cent, 
acoin solution are injected — are preferred by some, especially 
in syphilitic cases. They are more painful than the saline 
injections, more likely to cause conjunctival lesions, and 
they do not seem to be more efficacious. Sub-conjunctival 
injections enter largely, also, into the therapy of chronic 
uveal diseases (pp. 363, 367, 369, 370, 386), of certain 
corneal diseases (pp. 216, 218, 227, 235, 245, 246, 248, 
249, 252), and of some other diseases of the eye (p. 480). 
It has been held that the mode of action of saline in- 
jections is, that this solution is a lymphagogue, and hastens 
the lymphatic circulation of the eye. Those who favour 
mercurial solutions, hold the improbable theory, that these 
solutions penetrate the sclerotic by the lymphatic vessels, 
and act locally on the diseased tissues. The most probable 
and rational theory is, that subconjunctival injections, 
whatever substance may be used, act merely as local 
irritants, setting up a certain beneficial reflex hyperemia, 
which favours absorption of inflammatory exudation. Hence, 
they are indicated only where the hyperemia present is 
insufficient for this purpose, and a stimulus to the circula- 
tion is needed, but not where the hyperemia is excessive, 
as in acute uveal inflammations. 

* Haemorrhage in the Vitreous Humour. — This is often 

caused by blows on the eye, which rupture intraocular blood- 
vessels. It is the result, too, of certain diseases of the 
retina and choroid, which are accompanied by haemorrhages 
in those membranes ; or of disease of the coats of the 

32 



49S 



DISEASES OF THE EYE. 



[chap. xv. 



retinal or chorioidal vessels. It is seen in old people with 
atheromatous vessels, and it occurs in pernicious anaemia, 
syphilis, and malaria. Some quite healthy young people 
of both sexes, are liable to recurrent haemorrhages in the 
vitreous humour, which on ceasing either leave the vitreous 
humour clear, or it may remain more or less opaque. 
Strands of connective may form in it, and even detachment 
of the retina may ultimately come on. No explanation for 
these cases in young people can be offered. The arterial 
tension is often high, constipation is often present, and there 
may be epistaxis. 

Haemorrhages in the vitreous humour, when viewed with 
the ophthalmoscope, present the appearance of very black 
floating masses, between which the chorioidal reflex appears, 
and, if they lie in the anterior part of the vitreous chamber, 
they may be seen with focal illumination, and then are red. 
When the vitreous humour is full of blood, no red reflex 
can be obtained with the ophthalmoscope, and the pupil looks 
quite black. 

Treatment. — Saline sub-conjunctival injections afford the 
best hope of promoting absorption of vitreous humour 
haemorrhages. In recent cases rest in bed is important. 

Mouches Volantes, Muscse Volitantes, and Myodes- 
Opsia 1 are terms applied to the motes which people 
frequently see floating before their eyes, but which do 
not interfere with the acuteness of vision, nor can the 
ophthalmoscope detect opacities in the vitreous humour, nor 
any other intraocular disease. These motes are most apparent 
when a bright surface, such as a white wall or the field of a 
microscope, is looked at. Mouches volantes have no clinical 
importance. Those annoyed with them should be strongly re- 
commended not to look for them, as in that case others are very 
apt to become visible. They depend, probably, upon minute 
remains of the embryonic tissue in the vitreous humour. 



' nvta, a Jly ; 6<//is, seeing. 



CHAP. XV.] 



Til E VITREOUS HUMOUR. 



499 



* Fluidity of the Vitreous Humour, or Synchysis, 

is not rare. It can only be diagnosed with certainty 
when the humour contains floating opacities. Low tension 
of the eyeball does not always indicate fluidity of the vitreous, 
although soft eyeballs nearly always contain fluid vitreous 
humour. Trembling of the iris (iridodonesis) is also no sign 
of fluid vitreous, but merely indicates that the iris is not sup- 
ported in the normal way by the crystalline lens. Defective 
zonida of Zinn, however, is often caused by, or is a concomitant 
of, fluid vitreous, and, by causing displacement of the lens, 
would allow of trembling of the iris. 

The Causes of synchysis are chorioiditis and staphyloma 
of the chorioid and sclerotic, and it also occurs as a senile 
change. 

Fluidity of the vitreous humour is not, per se, a condition 
of serious import, unless the eye come to be the subject of 
an operation involving an incision in the corneo-sclerotic 
coat, when it renders prolapse of the vitreous more liable to 
take place. 

* Synchysis Scintillans is a fluid condition of the vitreous 
humour, with cholesterine and tyrosine crystals held in 
suspension in it. The ophthalmoscopic appearances are very 
beautiful, resembling a shower of golden rain. A satis- 
factory explanation for the occurrence of these crystals in this 
position has not yet been given. They usually occur in old 
people, and seldom cause any marked deterioration of vision. 

Foreign Bodies in the Vitreous Humour and In- 
terior of the Eye in General. — One of the most common 

and most serious accidents to the eye is perforation of the 
sclerotic, or of the cornea and crystalline lens, by a small 
foreign body (shot, morsel of iron, copper, stone, or glass), 
which then lodges in some part of the interior of the eye — 
very frequently in the vitreous humour. 

The danger of leaving a foreign body in the eye is great. 
It is rarely that, whether it remain free, or, as sometimes 



500 



DISEASES OF THE EYE. 



[CHAP. XV. 



happens, become encapsuled, it is tolerated permanently in 
any part of the interior of the eye ; and that event should 
never be reckoned on in the treatment of such a case. 

As a rule, foreign bodies in the vitreous, or elsewhere 
within the eye, soon produce violent inflammatory reaction. 
This occurs, either by reason of infective micro-organisms being 
introduced into the eye with the foreign body, or, it may 
be caused by the oxidisation of the foreign body, when 
it is of iron or copper. The form of inflammation may 
be either a plastic or a purulent uveitis, in the latter case 
with purulent infiltration of the vitreous humour and 
hypopyon. 

An eye which contains a foreign body that is not, or 
cannot be, at once removed, may be regarded as lost ; and 
such an eye becomes, moreover, one of the surest sources of 
sympathetic ophthalmitis, when plastic inflammation is set 
up. 

It is, consequently, of the utmost importance to decide 
whether or not a foreign body be in the eye ; and if one be 
there, to remove it if possible, should a reasonable prospect 
of saving sight, even partially, exist; and this too, with 
the least delay. 

Means of deciding whether a Foreign Body be in the Eye. — If 
the case be seen immediately, or soon after the accident, and 
there be no intraocular hemorrhage to obscure the view, the 
foreign body may perhaps be detected with the ophthalmo- 
scope in the vitreous humour or fundus oculi as a dark or 
glittering body, according to its nature ; and focal illu- 
mination with dilated pupil will often help us to discover 
a foreign body situated in the anterior part of the vitreous 
humour. Or, if it cannot be seen, an opaque streak through 
the vitreous humour, one end of which corresponds with the 
sclerotic wound,